Emilia regained her consciousness and opened her eyes slowly.

"We done?" she asked, as she looked around and searched for the members of her team. But none of them was around. A single unknown young woman was staring at her in confusion. The room she had woken up in wasn't even similar to the sterilized lab where the test had started and was supposed to finish. She recognized the room. It was used for robot repairs, and she had visited there a few times when working on Stirling.

"Wha -? AAH!" she screamed, which scared the woman staring at her. "Hey, what's happening here? Where am I?" Emilia asked her.

The woman was frozen and quiet. She was wearing an orange jumpsuit, the kind the test subjects were usually offered during some tests.

"What the... who are you?" Emilia yelled, but the woman stayed silent.

Looking around more carefully, Emilia began to notice parts of her own body were missing. She had no hands. Looking down, she noticed that there weren't any feet there either. She couldn't find any part of her body, or move anything other than a single eye and its eyelid. She couldn't even feel her mouth, but she was able to speak somehow.

"What's going on here? Where are my hands?" she screamed, "Am I? No, this can't be possible. Can it?" Realizing what had happened to her, she was scared like never before in her life, even more than when she was doing the SRL test.

She was a robot now, attached to a rail on the ceiling. This proved that the brain scanning test had worked, her mind was downloaded, and now, it was uploaded to a robot, about the size of a soccer ball, with two handles on each side.

Emilia was devastated. She closed her eyes and tried to think. Maybe the situation wasn't that bad. The fact that she was now a robot, and could remember things clearly, meant that the test was a huge success. She was upset because the protocols weren't followed, and the mind transfer had deprived her of a body. But there was hope. If her mind was intact, and working like when she was a human, perhaps it could be transferred back into a human body, or at least a human-like robot.

She realized that panicking may scare away the only human who was there, cause her to push a turn off button, or something like that. So, she calmed herself down and tried to speak. "Okay, let's do this properly. Sorry for my freak out."

Looking at the woman's face and her clothing left no doubt that she was a test subject, and had uploaded the data of a device containing Emilia's mind into a robot accidentally, without even realizing what she was doing. Emilia thought getting her to carry the robot to Aperture scientists was probably the right move. "I will explain what just happened," she told her, "but let's get out of here first. Can you pick me up?"

The test subject picked her up without saying a word. She seemed mute. "There is a hub not far from here," Emilia told her, "Let's go there."

As the test subject carried her through the halls, Emilia noticed that no one was around. Most lights were off. The whole place seemed abandoned. "By the way, where is everybody?" she asked, not really hoping for an answer. "Is the office closed? And what is a test subject doing here anyway?"

A little further ahead, there was no light at all. Emilia felt scared. Although the fact that even her Nyctophobia was scanned during the brain scanning test was solid proof of scientific success, that did little to relieve her. Her phobia was still with her, even though she was a robot now.

"That's really dark. Lights switch anywhere?" The test subject found a switch and pushed it, but there was still no light. "I mean we don't have to go through there do we?" Emilia told her, "I completely understand that you would rather want to find another way if you're scared of the dark. No shame in that. It's just the absence of light, right? What reason would anyone have to develop a phobia for it? Can't find another way though, hmm?"

Suddenly, Emilia realized something. Her living organs were gone, but she had new robotic parts now. "I may have an idea." she told the test subject, "Let me try something." Her eye turned into a flashlight and lit the way. "Woah, it worked. That's crazy!" she said with excitement, "I still don't like this plan but here we go."

The test subject carried her forward into more abandoned offices. "Wandering through the office after working hours with a stranger and nothing more than a flashlight..." Emilia spoke her thoughts, and then turned her eye towards the test subject. "Listen I'm sorry for..." she realized that the flashlight was pointing right at the woman's eyes, blinding her, and turned it off, since the dark section was behind them now, "Oh! I'm so sorry, my bad, I didn't mean to overexpose your eyes."

Emilia was going to thank the woman for bringing her to the staff, since she was sure they were waiting behind the next door. But there was no one there. A large waiting area with guards and maintenance staff was supposed to be there, along with an elevator to the surface. But there was just a small room she hadn't seen before, with a door and a window, and some computers.

"Okay! Wait, what happened here?" she asked in confusion. "Look at the window please." The test subject held her in front of the window. They were at the bottom level, deep inside an underground hole, exactly where they were supposed to be, but instead of an elevator, there were tall structures there, so tall that she couldn't see the top of them.

"Alright, trying not to panic again. Can you tell me what year it is?" she asked the test subject, who only shrugged in response. "Oh, you don't know either? Guess we're on the same boat then." It was terrifying to know they were both lost in time, if not space, but somehow comforting to know they were in the same boat together. That meant they needed each other, and the test subject couldn't throw her away like a useless object.

Emilia paused for a moment to evaluate the situation. She wasn't even aware of any plan for constructing such tall structures in the Enrichment Center. But they were there, and they didn't even look new. Many decades must have passed since her mind was downloaded, probably more than the possible lifespan of any person she knew. The thought was terrifying, but she decided to focus on what could be done about the situation.

"Let's try to get this door open." There was no handle, so she searched for another mechanism, and noticed a plug on the wall. "Stick me on that plug on the wall," she ordered the test subject. "I'll see what I can do."

It was a perfect fit. She got connected to it and gained access to some devices. It came with the heavy sense of being a robot and having a digital mind.

"Got it!" she yelled victoriously, and the door opened a second later. The test subject picked her up and carried her outside. They stared at the large and tall structures and pipes. Most of the area was empty in the past, as Emilia remembered. The staff used it as a place to smoke, play ball games or simply gather and talk away from camera sights when she was still a human. "None of this used to be here," she said with a sad voice. "How long was I out for? It must have been decades!"

Emilia remembered that the rails which were installed in the facility allowed the robots to access the Enrichment Center's network, and move around on them. That could have answered some questions. "I really don't know where we are going now. Let's try to find a management rail, then I can access the whole network." Emilia told the mute woman, as she climbed some stairs to enter an unknown building, and found a small elevator there.

"Elevator, sure. What's the worst that can await us up there?" But after thinking for a second, she realized that the answer was actually frightening. How would the employees or robots react to a rogue test subject wandering unsupervised in the facility, and a robot uploaded with sensitive information about the company? How would they respond to such a threat? She knew that her human self would have never allowed such a threat to escape. "Actually, you don't want to know," she said, as the test subject entered the elevator.

The elevator was slow, and the woman held Emilia towards herself. Emilia looked at her more closely and paid more attention to what she was carrying. It was a device called a Portal Gun. It could generate portals on certain surfaces, connecting them together, enabling people to enter one, and exit the other. Aperture science had developed it years ago, but it was never mass-produced, since they realized that a small flaw or damage can could cause it to create a black hole, sucking all of Earth's mass in a few seconds. But her Portal Gun looked more advanced.

"Can I ask you something real quick?" Emilia asked her. "What Portal device model is that? Doesn't look like any of the ones I've seen before. Looks cool though. Design team did a good job. Engineering too. Very slim fit." The woman stayed silent.

When the elevator stopped, Emilia noticed a rail on the ceiling, and yelled, "Oh! A rail! We found one!" as the woman attached her to it.

Emilia turned like a ball and said, "Woaah! Feels weird. This will take some getting used to. Thank you test subject."

She was now connected to the network, and to her surprise, the system recognized her as an Aperture scientist, which gave her access to a vast amount of data, as well as the ability to control some instruments in the facility.

Realizing that she should spend some time analyzing the data from many years, and the fact that the area ahead wasn't built for easy access, making it impossible for the test subject to carry her through, she said "I hope I don't intrude if I join you for a bit, while I try to get a sense of what happened to me, the facility and you."

The test subject moved to the area ahead and began creating portals to travel between unreachable surfaces, as Emilia began moving on the rail and reading the data. She now had access to cameras and loudspeakers, allowing her to monitor the test subject and speak to her from afar.

"So, again I'm sorry for my erratic introduction. I'm Emilia Conly and I work in Aperture's research group for artificial intelligence... well, I did. Until now. See, my main contributions were in the field of brain scanning and it seems like one of my old scans just got loaded into this robot. I knew the risks of this happening. We enforced strict backup removal routines so we wouldn't accidentally clone our minds, but here we are."

Emilia found the old files relating to her own brain scanning test and read them. The contents were horrifying. "Really struggling to hold back the panic now!" she told the test subject, who was struggling to make her way through places which most of them weren't designed for human passage.

The brain scanning test, which was the last thing she remembered doing as a human, was a success. She had woken up from a coma exactly on the planned date, completely healthy. Her mind was encoded to be stored as synthesized strands of DNA. But it took the research team a very long time to decode that data and turn it into a digital format. By that time, the protocols regarding the treatment of stored minds were forgotten, or replaced with new ones, which saw the stored minds no more important or special than any useless data written on a disk.

It was finally clear why Caroline was so insistent on turning human minds into AIs. The medical files showed that her husband, Cave Johnson, the CEO of Aperture Science, was sick and dying. Caroline wanted to save her husband by turning him into an AI.

It was difficult to learn what finally had happened. There was an official date of death for Cave Johnson, shortly after the brain scanning test, but there were other records showing that his health was being monitored, and his organs were being replaced by robotic parts, after that date. It was impossible to tell what had happened to him with the data at hand.

But the shocking part was the fate of the whole Aperture Science facility. Fighting another panic, Emilia hardly brought herself to read it to the end. The technology that her human self developed had brought the end. All the advances in the fields of artificial intelligence and brain scanning had led to the development of Genetic Lifeform and Disk Operating System, or GLaDOS. The records weren't clear, but it seemed that Cave Johnson had ordered the scientists to incorporate Caroline into GLaDOS, even without her consent, in case he died before her.

The name Emilia Conly was recorded as one of the lead scientists working on GLaDOS. The exchanged E-Mails showed that Cave Johnson and Caroline had ordered her to create it as soon as possible. The development was a scientific success, but almost as soon as it was activated, GLaDOS gained access to the entire network of the facility and released a large amount of neurotoxin, killing everyone. Since her human self was there for activating GLaDOS, it was safe to assume the human Emilia was killed too.

After that, GLaDOS had performed a series of dangerous tests on human test subjects, and the remaining trapped staff. Eventually, one of the test subjects had escaped the test chambers, and had made it to GLaDOS, disabling it. After that, autonomous robots, designed to maintain the facility, had taken care of it to some degree, but there wasn't any sign of human activity anymore. Maybe it was because of the fear of killer robots, dangerous toxins and chemicals, the radiation leaking from the unmaintained sections, or something else, but in any case, no human had entered the facility since the activation of GLaDOS. It seemed like the whole place was abandoned.

Emilia was ashamed to see her own rule in the catastrophe. After awakening from the coma, her human self had dedicated many years of hard work to something that eventually brought the death of her, along with a large number of innocent people, annulling an unimaginable amount of work and scientific achievements which could have been used to help humanity.

Realizing she owed the truth to the test subject who had brought her so far, she decided to inform her about everything. Watching her on a camera, she said, "I read the records of what happened while I was out. Everyone is dead. All of them! And it's my fault! See, I worked on her. I created the Genetic Lifeform and Disk Operating System just like Cave wanted... well, my human self did. I have no memory of this, but the records are clear. Caroline never consented to be scanned in, but somehow they must have found a way around that. I need to process this for a bit and figure out what to do now. See you in a bit."

At this point, Emilia was desperate and couldn't see a reason for going on. All her dreams were shattered. The things she considered her achievements in life had turned out to be destructive. She couldn't see anything to fight for. She was trapped deep under the ground, and no one was waiting for her outside.

As Emilia was about to give up, she came across some files which gave her a purpose. Some human test subjects were still down there and had been for years. They were unconscious, and in a state that the system described as "Stasis mode". She could monitor their life signs, which indicated they were alive and could come out of the hibernation-like state. The test subject who had uploaded her stored mind into a robot was probably among them not so long ago and had risen from the "Stasis mode" somehow. She could at least help them, along with the test subject who was already struggling to escape.

Aside from the organic life, there were stored minds in the Enrichment Center. Reading the names, Emilia noticed that some of her old colleagues were among them. The fact that a computer was simulating a human brain so accurately that she felt alive, with her mind functioning like when she had an organic brain, gave her hope. All those dead people could have been resurrected as AIs.

As for her, things were complicated. Who knew? Maybe there was a chance to find a body inside or outside the facility, and become a little more human. She could still pursue science, and make something out of her life with the second chance she was given.

Realizing these facts, she became determined to survive and tried to help the struggling test subject. She moved on the rail alongside her and helped whenever she could by opening doors, activating different instruments, and lighting places with her flashlight. The test subject had to go through some test chambers, but Emilia found herself unable to guide her there. The robot was programmed not to help any test subject during the tests, and she couldn't bypass that programming.

As they went up little by little, they felt earthquakes and sounds of explosions from upper levels, and some debris fell down every now and then. Something was going on there.

Emilia tried to find information about the test subject she was working with. But there wasn't any profile which matched her in the archive. She hadn't said a word so far, and seemed mute.

They arrived at a place where Emilia's office was located. It was dark, so Emilia used her flashlight to light it. "Have not been here in a while." she said, and realizing the familiar surroundings, continued "Wow, this place hasn't changed a bit... Ah yes, the boring presentation room. For some reason, the presentation rooms were assigned special roles. This is the boring one where only uninteresting topics get presented. I worked next to the 'presentation room of danger'. Well, that's it nickname. What they pitch there is shocking at first, but it didn't take long for me to get numb to it."

As they continued forward, they saw some mannequins at an unusual place. "Mannequins?" she asked, as that gave her an idea. Mannequins could have been used for a certain research purpose. "Hmm, interesting. You reckon I could find a humanoid android body somewhere around here? Forgot what it feels like to have hands."

She kept staring at the mannequins, and it took her a little to realize the test subject had already moved ahead. "No hands, only handles," she said with sadness, as she followed her.

They arrived at the bottom of a large structure, built on top of another structure. Entering it, they found it very tall, but mostly empty. "Oh no. I believe this might be an old dangerous teleportation experiment." Emilia told her companion. "Here, we got ourselves the Aperture Science Nonlocal Matter Displacement Device. Quite a mouthful, I know. Our team affectionately dubbed it 'the Spire'. Adds a bit of pizzazz to it, right? It was developed as a successor to the Borealis experiments from the 70s, but I never seen it with my own eyes. Well, I've still not seen it with my own eyes, unless digital cameras count."

Emilia was able to climb the structure on a rail, but the test subject had to create portals on different surfaces and jump in and out of them to get to the top. Once there, they realized that the bridge connecting the old Spire to the upper part was gone. Corrosion had taken its toll over decades.

Emilia had an idea for going forward, but she was ashamed to tell it to the test subject since it required her to risk her life, but the woman was able to figure it out on her own. She created one portal on a wall facing where they were headed, and another portal at the bottom of the old Spire. She jumped down from the top, as Emilia screamed in fear, and managed to enter the first portal, and immediately exit the second one with a high speed, which caused her to be thrown all the way to the other side of the chasm.

"Woah! That was close!" Emilia told her. Realizing that there was no rail, and she had to find another way there, she continued, "We better get going. Let's find a way up to the surface. That's where we'll find the control room."

While searching for a route for herself and the test subject on a map, Emilia noticed a shortcut. She spoke through the loudspeakers while monitoring the test subject using cameras. "This will sound stupid, so just bear with me. Garbage disposal tubes generate much more force than the ones in test chambers. Should be able to carry you. If you jump into this tube, I will route you to the upper layers of the facility... Maybe hold your breath."

The test subject trusted her and jumped into the tube. A powerful air current carried her, and after going a long distance and taking several sharp turns, she was thrown to a chamber in the upper levels. "This is as far as I can get you," Emilia told her, while she monitored the test subject. "Damn it, that's barely halfway. Well, looks like we have to go the long way. Sorry."

Emilia noticed something strange on the network. The status of another much newer Spire on upper levels had changed to "Activating". Realizing, it could take the test subject a long time to navigate her way through the abandoned facility, solving old tests, and finding her way around locked doors or ruined areas, she said, "I'm going to research this Spire thing while you solve the chambers."

This was the first time she was examining a science document after becoming a robot. She was excited to know what science had achieved while she was out. As soon as she started researching, she found herself unable to hold back her excitement. "I found some internal documents for the Spire," she broadcasted through a loudspeaker for the test subject to hear, "which is 20 MEGABYES large! How did they figure out to fit all that on a single drive?"

The advancements made in computer science after she was gone were unbelievable to her. She imagined about the possibility of accomplishments with such a science, and it excited her for a moment until she realized none of them had been made, and the whole facility was in ruins. The fact that such a large and important facility had remained abandoned during all those years worried her. It could have been a sign of humanity's downfall.

"I read up on the Spire," she continued, "One thing puzzles me. How did it get activated? It's been dormant for decades and suddenly it just kicks itself into action? Whoever it was must have really upset it."

The mute test subject couldn't answer her. She kept finding her way up, towards the surface, going through paths intended for this purpose whenever possible, and finding a way around barriers, whenever that wasn't an option. She had to go through some test chambers and maintenance areas, risking her life to move forward.

Suddenly, the ground shook again, and the lights started blinking. Colorful liquids began erupting from every hole in the old pipes, indicating that they were being used again, after a long time.

"There it was again. Did you see?" Emilia asked. "The Spire is stealing resources from down here as a part of its power-up sequence. I don't think it presents an immediate threat to us, but … something just feels off. Aperture likes to poke around at everything, no matter how dangerous it is. The fact they discontinued this experiment doesn't really fill me with emotions I would categorize as 'positive'."

The test subject found a small service elevator and used it to get to the upper level, while Emilia used the rail to get there. On the way, she explained, "Did you know that Aperture simulates breathing and blinking in its sentient robots? I still have a sort of subconscious reflex to breathe and blink my eye, even though that's not technically necessary. Turns out that the human mind doesn't cope well when those functions are removed. Be glad you didn't volunteer for our early mind mapping tests. Those were not good times to be a test subject."

The test subject had to solve a few tests, involving puzzles and getting to unreachable surfaces using the portal gun and some gels which gave surfaces different features, including making them extremely slippery, bouncy or allowing portals to open on them. After solving them, the test subject had to go through a narrow corridor, under a loudspeaker. Suddenly Emilia's loud voice filled the corridor. "Well done test subject!"

The robot Emilia recognized her own old voice, and screamed "No! Turn it off!" She was embarrassed to listen to her own self, as the voice continued, "You have just completed another test. Congratulations on contributing once again to the future of science." Her old self sounded very enthusiast and warm on the prerecorded tape which was being played, unlike her present self, who screamed, "I thought they threw these lines away! Why is it so loud?!"

The tape continued playing, "Feel welcome to pause at any moment. There's cake and beverages in the break room." Emilia yelled at the test subject, "Turn it off! Turn it off! TURN IT OFF!" Until she realized the test subject was staring at the camera confused, and unable to do anything, and she was in control herself. "Looks like I turned myself off. Yeah … I dabbled in voice acting when I first joined the company as an intern. That was so long ago! Please, just forget everything you heard down there!" and they continued forward.

Finally, they arrived at an elevator which was able to carry them to the surface. The test subject reached there by solving puzzles, jumping across wide chasms using portals, and risking her life in the process, and Emilia had simply moved on a rail. They had climbed so much that the bottom of the hole they had started in wasn't visible anymore.

"Hey hey!" Emilia called the test subject. "I need you to carry me up the elevator. We've done this before, so be ready to catch me." She detached herself from the rail, and the test subject caught her. "We are becoming quite good at this!"

As they entered the elevator, which started to take them up, Emilia felt she missed the car park, and couldn't wait to get there. From there, it was just a small walk to the control room, which allowed them to take command of the entire facility, and hopefully, contact the outside world.

This had been a frightening journey. The mute test subject had been nice, but Emilia was desperate to see more people and talk to them. To her surprise, the elevator stopped shortly. "Umm... That's not the surface. Is the elevator stuck?"

The test subject walked out. They were inside a building, which wasn't there when Emilia was still a human. A window to the outside world showed them the situation, as well as some afternoon sunshine. There was no car park there anymore. There was just more Aperture buildings and a chasm which went down all the way to the bottom. All the buildings seemed abandoned and half-ruined. Vegetation had grown all over the place.

They still hadn't appraised the situation, when a cracked monitor got activated, and they heard a robotic voice. "Oh, I found you." The sound was funny. A robot, in a similar chassis as Emilia, appeared on the screen. Aside from the color of the lights on its digital camera, there was nothing to distinguish it from Emilia. The new robot's lights were yellow, and Emilia's lights were blue.

"Who is that now?" Emilia asked in confusion.

"I was quite worried where that teleport could have left you." The robot spoke to the test subject with the same funny voice. "At least you didn't suffocate in a wall, so that's good. Tell you what. Why don't you come back and join me in the Spire? I'm charging up the teleporter as we speak to continue our mission you so rudely interrupted."

"Wait, what mission?" Emilia shouted.

"Oh, who is your little sidekick? Cute. You can join us if you want."

"Join you with what?"

"Oh, we just want to repair the facility. I will pick up the remains of our former central core, reassemble her, and bring her back to life."

"Wait, who are we talking about? Are you talking about GLaDOS? You want to bring back GLaDOS?!"

"That's what the humans call her, yes."

The monitor exploded as soon as the robot finished his sentence. Given the poor condition of the whole place, it was surprising that the monitor had worked at all.

"Woah! And that's why you gotta switch your capacitors!" Emilia said sarcastically, and asked the test subject, "So, that's the sort of guy you normally hang out with? Did you work with him?"

The mute woman couldn't answer her and walked out of the door. They were in the open now. They had a clear blue sky above them, but they were surrounded by a chasm on one side and a half-ruined building on the other side. There was a metal passageway around the building, but it was barely standing. The test subject walked on it. Emilia looked down the deep chasm for a moment and then closed her eye immediately. "Oh! I shouldn't have looked!"

They arrived at some offices which were mostly ruined but seemed to have some active electronics. There was a rail there.

"Put me on the rail over there. I'll open the door for you."

The test subject attached Emilia to the rail, and she regained access to the Aperture network. She opened the door for the test subject, as she tried to analyze the situation.

"Right, so you are who activated the Spire... I … I should have seen that coming. Is he really trying to bring back GLaDOS? He's right about one thing though. The facility is already barely holding together, and that won't change unless we put someone in charge of the central core. But why her? Why doesn't he just take the crown for himself?"

They had fought their way out of the underground facility, believing they would reach their freedom on the surface, but now, they were trapped in a labyrinth of ruins, failing infrastructure, deep holes, rogue robots and pits filled with acids and dangerous chemicals. They had to keep fighting for their lives even harder on the surface. Going forward meant walking through dangerous test chambers.

The prospect of a killer robot gaining the control of the whole place was terrifying. Emilia realized that there can be no salvation for them as long as such a threat existed. GLaDOS had already killed her once, when she was a human, and there was no reason to believe a better fate awaited her if it gained control over the facility again. She knew that GLaDOS was actually Caroline, at least partly, and was eager to bring her back to life. But putting a machine which had committed a mass murder in charge, before knowing what was wrong with it, was something they needed to stop.

"I don't blame you for helping him." Emilia told the test subject, "You didn't see what she did … I mean neither did I … but the records are disturbing. Took her less than a second to seal the fate of every human in the Enrichment Center."

Studying the records didn't tell her anything about the reason GLaDOS had decided to kill everyone by releasing neurotoxin into the ventilation system. The records showed that the decision to integrate Caroline's body into the Genetic Lifeform and Disk Operating System was hasty, and couldn't have been taken with considering everything. Caroline had become part of a machine while she was still alive. Her body couldn't have lasted all these years, but if the machine had read her mind, and integrated it into its own artificial intelligence, as it was intended, it was possible for Caroline to come back to life as an artificial intelligence, just like Emilia had.

The goal of bringing Caroline back to life seemed very noble and exciting to Emilia, but only for a second. She wondered if Caroline even wanted to come back. What if she didn't want to live as an AI in the first place, or regretted it as soon as it was accomplished. Maybe that was the reason she went mad. At any case, bringing her back wasn't something that could be done responsibly without studying GLaDOS carefully, and it certainly couldn't be left to a robot which probably didn't know the consequences.

As they were making their way to the Spire control room, seeing how the facility was falling apart saddened Emilia. She realized that if she had acted responsibly during her life as a human, things would have been different; the ruined laboratories could have been still operational, full of eager scientists and students trying to help the humanity, and their achievements could have helped billions of people.

"I just … I just wish I could go back, you know? To amend mistakes," Emilia said with a sad voice.

They reached a point where the rail direction was separated from the way the test subject could go. "We might not see each other in the next test chamber. Whatever he says, or has already said to you, we CAN NOT allow GLaDOS to return."

They each went their way, while Emilia realized her network access was limited considerably. She couldn't think of a reason, other than the other robot trying to block her out. She tried to study every action she had access to, and conclude what the robot was up to. How was bringing back GLaDOS related to the Spire? That was a question she needed to answer in order to proceed. The human probably knew the answer, but was not able to speak, so she needed to find out on her own.

After some study and putting various seemingly unrelated data together, she found the answer, and it only frightened her further. The Spire, which had never worked properly while humans were still around, was a decaying unstable machine on its own, and a slight failure in it could have resulted in the formation of a black hole on Earth, was about to be used to teleport various parts of GLaDOS together and reactivated it.

Emilia managed to temporarily link up with the test subject again. "Finally found you again!" she shouted, "I have got some news. He wants to use the unstable Spire teleporter to put together GLaDOS, right? If we can go into the control room and cut power from the core, we have a real chance of preventing a catastrophic meltdown."

The rail didn't let Emilia to move along with the test subject, so they had to found their ways separately. After studying the map of the relatively new surface structures, Emilia found a safe route for the test subject to get into the control room. She was blocked out of the cameras and loudspeakers, but when her path crossed the test subject again, she told her the plan "I'll prepare an escape route for you that will take us straight to the Spire. Meet you there!"

As Emilia was moving in the maintenance section she heard a large metal door the test subject was supposed to pass through closing and went back to see what had happened. She heard the robot's voice again.

"So, I have decided. You betrayed me. Twice! I have given you enough chances! Something tells me your new friend managed to turn you against me, so I'm just going to … kill you … now … before you become any sort of threat. Again, thank you for your help, you served us well. Now, you might be thinking: 'But Stirling? Stirling my dear, how am I going to die?' And the answer will be simple. I will use this teleporter, the very one that you activated, to teleport you to some place that will lead to your immediate demise. Now, I realized, I didn't quite answer the question, but that's because I will let you decide. I have a few options here…"

As the robot was gibbering, Emilia realized that the test subject was trapped in a small room, and a part of the wall was not fixed in place, but was held by a robotic arm, and could have opened whenever maintenance work was needed. She still had access to the maintenance functions, and opened that section.

"Psst! Over here!" she called the test subject and pointed at a wall behind herself with her eye, indicating that it could support portals. The test subject quickly created one portal in the room and another one at the wall behind Emilia, and escaped to the maintenance section.

"No, no no no!" the robot screamed on a loudspeaker, "Don't do that, where are you going?"

As they were running away, Emilia asked, "Wait, did he say his name was Stirling? I built a vacuum cleaner once, called the little guy Stirling."

There was no time to waste. They hurried to the control room. The rail ended right before it. "Hey, over here. Come and grab me. No rails in the chamber," Emilia told the test subject. "You ready for this?"

They entered the Spire control room. The top of the Spire, which contained the core, was visible from a window. It was located in a huge vertical room which went down a long way, into the underground facility.

"Welcome ladies, welcome … to your demise." The robot spoke through a loudspeaker, "Let's cut the preamble and get to it. Any last words?"

"Yeah, I have some," Emilia said joyfully, "Is it possible that you were once a vacuum cleaner?"

"Uhm … How do you know that?"

"Ha ha! I can't believe it … Awww … They grow up so fast! It's not polite to murder your mother!"

"You're my … But how's that possible? I was created by a human!"

"I can't believe my roomba is trying to kill us …"

"Yes, about that … The Spire is still charging … Just give me a minute, I'll murder you as soon as possible. What did you even think by coming here? Thought you could just press a button to stop me?"

"You mean this button?"

"What button?"

Emilia and the test subject stared at what was in front of them. "Big and red. Right in front of us."

"That's not a button. Ignore it. Don't look at it."

"What happens if we press it?"

"Nothing! Don't press the button! It's really boring, believe me."

"I say we press it."

"Don't press it!"

"Alright, before we press any buttons, can you put me on this claw in the corner?" Emilia asked the test subject. "I have an idea."

There was a robotic claw there, and its arm went up to a hole in the ceiling. As the test subject held Emilia in the position, the claw closed and carried Emilia out. "Good," she said, "Now that your hands are free, I say we give that button a little push while I explore this magnificent vent."

The test subject pushed the button, and the Spire's core opened, revealing large pipes and wires which were charging it.

"That's one satisfying button!" Emilia shouted, as the claw turned out to be connected to a crane, and carried her into the vertical room. She knew what had to be done.

"I told you not to press it!" Stirling yelled with a furious, yet funny voice, "That's it … Time to die. Enjoy your last moments! You'll die in 5 minutes!"

"The fight is on," Emilia told the test subject. "We need to disconnect all of those pipes before the time runs out. Here, through this door."

She opened the door for the test subject to enter the Spire's large vertical room. There, the test subject created portals between different surfaces and started traveling between different sections in order to get to the controls and disconnect everything from the core.

"What are you doing? Do you really think you can stop me?" Stirling cried, but no one paid attention to him. "You look ridiculous," he told Emilia, who was hanging from the claw.

"Seems about adequate considering I'm fighting my own vacuum cleaner."

"So, here you are. You're just back now? Where have you been?"

"What are you talking about?"

"I didn't see you again after you upgraded my chassis. We used to do everything together."

"Do everything together? You were a vacuum cleaner. You cleaned up for us." turning towards the test subject, Emilia added, "Don't even ask me why we gave him consciousness."

"You didn't even say goodbye."

"Are you having abandonment issues right now? Is that seriously what's happening? I built a vacuum cleaner with abandonment issues!"

That seemed to have angered Stirling. He had a number of robotic turrets armed with machine guns ready in one of the control rooms, and ordered them, "Go turret! Kill!"

"He's in quite the murderous mood today," Emilia said sarcastically.

The turrets were too slow and clumsy. The test subject easily kicked them away, or went behind them, using portals.

"Argh … Pathetic," Stirling cried.

"Almost done," Emilia screamed, as the time was running out. "One more to go. The last control room is right here. Come on, you can do this!"

"No, you can't do this," Stirling told the test subject, "Remember that brain damage test we did? Where you had to push a button? Turns out I was wrong. You must have brain damage. Why else would you do this to me?"

"Ahhh, don't listen to him!" Emilia said. "Can't have slept for that long, right? RIGHT?! Oh … maybe that's why you don't talk."

"That explains a lot … Oh! A red button! I HAVE to press it because I'm so brain-dead that I need to stimulate my soggy brain with satisfying click sounds and tactile feedback … That's you by the way … In case you didn't get it."

"Oh, I got it don't worry," Emilia responded giggling.

"Come on! Final button!" Emilia shouted at the test subject, then told Stirling, "You're right though. It is quite pathetic that a button pusher is your arch nemesis." Realizing what she said could have offended the test subject, she continued, "No offense to you, test subject. Just the reality of the situation."

"I'm not even going to respond to that," Stirling responded, with a disappointed voice.

"I mean, she's the only one of us who can press buttons. I don't have hands either… Wouldn't underestimate someone with arms."

The test subject pushed the final button right before the Spire was fully charged for usage.

"You did it! Haha! Yes!" Emilia screamed in joy.

"Yes, you did it. You shattered my dreams of rebuilding my home. Are you happy now? Proud of yourself?"

"Look, we also wanted the best for Aperture. But we can't do that by reactivating GLaDOS. It's not right. You know what she did."

As soon as Emilia finished her sentence, the ground started shaking, and the Spire made loud noises.

"What's going on?" Stirling asked in confusion.

"Uhh … Oh My …" Emilia couldn't finish her sentence. There was a blinding flash of light, followed by absolute silence, followed by darkness.

After a few seconds, Emilia turned on her flashlight. The power was out. Luckily, the crane had a charged battery, and she directed it to put her on a rail. The whole facility seemed dead. The test subject was unconscious and injured from the explosion. Emilia had no idea what had happened, until she passed by a window.

They were on the moon. The Spire was charged enough to teleport itself, and a part of the facility surrounding it, to the moon.

Aside from that, Emilia finally found out what had happened to the missing astronauts back in the 1960s. They were teleported to the moon successfully, the part facing away from Earth to be more exact, but the Spire couldn't teleport them back. Their bodies in spacesuits were just outside the window.

Since the metal doors leading to the Spire were sturdy and could function as airlocks, at least to some degree, the air was still breathable, but it was slowly being sucked outside, and the temperature was gradually dropping. The test subject couldn't survive much longer in such an environment.

Emilia connected the crane's battery to the system and managed to bring up the control room computers. An analysis of the network showed what was available. A few devices with solar photovoltaic cells were inside. Emilia used the claw to put them outside, where they could generate electricity using solar power.

Then she attended to the test subject. She grabbed her unconscious body with the claw and dragged her towards a stasis chamber at a lower level. Emilia knew that soon, there would be no air left, and no air meant no sound, so she recorded a voice message for the test subject to hear, when and if she woke up.

"Hi! Hello … Ah … I don't think you ever told me your name, did you? Look, I'm recording this on the off-chance that you actually survive. You were badly wounded in the eruption. I tried what I could, but … I've never seen anything like it. I'm a neuroscientist, alright? My expertise starts and ends at brains, not bodies. Look, the best I can do right now is to put you in stasis. It might help you heal, but … yeah … it's not looking good."

Her voice was sad, as she continued, "I'm sorry, okay? I don't know what to do now. The Spire is broken, so we're just stuck … on the moon. I guess this is goodbye. For now! Just for now. Take care."

Emilia put the test subject on the stasis bed, and closed it, sending her to a hibernation-like state. The stasis bed looked like a glass coffin and could shield her from the vacuum, keep the temperature suitable for a human body, and regenerate oxygen, using little power. But that little power was all that was available. In order to keep the stasis bed active, Emilia had to turn off everything else, including herself.

"At least I fixed something," she thought to herself. If they hadn't stopped Stirling, he would have brought back GLaDOS, or even created a black hole on Earth, destroying everything on it.

There was no way to communicate with Earth anymore, and her battery was running out. Emilia thought about her life for a while, the one she had lived as a human, and the one she had lived as a robot. Although she had no memory of what had happened to her human self after the brain scan, she had a general idea of how she had lived, and it made her sad. The human Emilia had been so focused on a few things that she forgot the bigger picture. Science had offered her unlimited possibilities to help herself and others, but instead of using it properly and responsibly, she and her colleagues were selfish and blinded by their own interests or narrow mindedness.

She had used her second chance after coming back to life as an AI to fix things, at least partly. With a determination to use her third chance, if she gets it, to change things for the better, she turned herself off.