It has only been a month since Chell was released from Aperture, and for some inexplicable reason she often finds herself missing it. She has a normal life now, or what passes for one, with friends and a job and her own apartment. It's a small apartment, with just one bedroom, and her only company at night is her Companion Cube. She likes to talk to it, even though it doesn't talk back, and the thought never crosses her mind that someone might be listening.

But of course someone is. Someone who always has been, and someone who always will be.

"And I also don't think that guy had any right to treat Sandra that way," Chell says, continuing to hand-wash her dinner dishes as she does so. "But of course he's a customer, so he's always right and all that shit, and we really couldn't do anything about it." She sighs as she finishes up, then turns to look at the cube, which is sitting on the sofa. Giving it a smile, she comes over and sits next to it, wrapping her arms around it in a hug like it's some sort of stuffed animal. The fact that it's made of metal doesn't bother her. The cube is comforting.

She turns on the television. It's small, a hand-me-down gift from one of her friends, and she can't afford cable, but she doesn't mind. She rests her head on top of the cube and closes her eyes as the Wheel of Fortune theme song plays.

And then the song is interrupted by a loud shrieking noise, emanating from the cube. Chell jerks her head up and away as she leaps off of the couch, backing away with fear as the cube continues shrieking. She covers her ears, even though it doesn't help much, and squeezes her eyes shut, hoping it will stop.

All of a sudden, it does, replaced by a familiar robotic voice. "I don't know if you can hear this, but sensors indicate you are within range. Hopefully you're not deaf as well as mute, because that would be entirely inconvenient." But GLaDOS's voice doesn't sound right to Chell. The snide remark is rushed instead of cocky, and the AI sounds almost panicked. "Look. If you can hear me, just…just place your hand on top of the cube. All right?"

Chell bites her lip, wondering if this is some sort of trap. After all, she never guessed that her beloved Companion Cube had sensors on it that could tell where she was, and now GLaDOS wants her to go near it? What if pressing the heart releases deadly neurotoxin or something?

"[Subject Name Here]?" the AI asks. "As previously mentioned, I need you to—AAAAAAA!" Her voice is cut off by a terrified scream that could only belong to her, and with her mind and heart racing, Chell rushes forward and slaps her hand down on top of the cube, which is warm for some reason instead of cold and metallic like she's used to. For one horrible moment there's silence, and then GLaDOS speaks again.

"Good. You can hear me. Of course, I didn't really think that you couldn't. I also know you're not mute. I've heard you speaking to the Weighted Companion Cube. Did you know it won't talk back?"

That sounds like the GLaDOS Chell knows, and she bites back a retort, reverting to her old policy of never giving any Aperture AIs the satisfaction of hearing her speak.

After a moment, the AI sighs. "Fine. You won't talk to me? That's just fine. I don't want to hear about your stupid human life anyway. It sounds droll, from what I've heard of it…and I don't need you to speak. Just listen."

Chell nods, not sure GLaDOS can see her but hoping the AI can figure out that of course she's listening, even as Wheel of Fortune continues to run in the background.

"My facility has been infiltrated," the AI says, sounding both bitter and miserable. "And as much as I'd like to take care of the problem myself, I can't. I need your help."

Chell inclines her head as a way of asking why.

"Well, not your help, specifically," GLaDOS continues. "Any human would do. But since you're the only—I mean, the last—human to leave the Enrichment Center, you are the most likely to return. Particularly since you still seem to be attached to your Weighted Companion Cube, despite having human company."

Chell rubs her hand along the top of the cube fondly. It's true that she is attached to it. Maybe if she were closer to her friends from work, or if she had a boyfriend, she wouldn't be, but she is.

"So I need you to come back," the AI says, sounding like she has to force the words out. "I promise not to harm you in any way. I need you."

How about once I fix whatever's wrong and you don't need me anymore? Chell wonders with a frown. But she remembers that GLaDOS has let her go in the past, and she figures that if the AI still wanted her dead, she would probably be dead by now.

"Please?" GLaDOS asks. Chell has trouble not laughing at how miserable the AI sounds. "I won't beg for your help, you know. There are other test subjects that could help me. And none of them are dangerous lunatics."

Chell doesn't believe a word of it. She knows GLaDOS has never let anyone else go, knows every other test subject was murdered during testing the same way she herself almost was. That means that she is the only one that can help the AI.

She sighs. Some part of her thinks that GLaDOS deserves to suffer. But she remembers the potato, remembers Caroline, and she thinks differently. At some point, the AI became her friend—although Chell doesn't know if she stayed her friend once Caroline was gone—and she feels like she has to go back to help her.

That and the fact that after Aperture, her "normal life" has been just as droll as GLaDOS imagines. As much as Chell has tried to throw herself into it, she just doesn't enjoy it as much as testing, dangerous as it was. It was the danger that was the exciting part, and taking orders at a restaurant just isn't the same.

"If you'll agree to come and assist me, tap the top of the cube three times," GLaDOS says. "If not, tap the side." She sounds nervous, like she's really worried that Chell will refuse, and after hearing that horrible scream, the former test subject can understand why.

Chell doesn't need to consider it anymore. She taps the top of the cube three times, then moves her hand away, and there is a noise that sounds a lot like an exhale. "Good. I trust you remember where the entrance is? After all, it wasn't that long ago that I let you leave. Out of the goodness of my heart, in case you've forgotten. So just come and—AAAAAAA!" There is another scream, and then nothing but silence. Chell waits for the AI to return and finish her sentence, but when there is no response after a few moments, she gets worried enough to speak.

"GLaDOS?" she asks, but there is still no response. That makes it clear that the AI isn't faking and something bad truly has happened to her. With a frown, Chell turns and runs out the door as Wheel of Fortune goes into its first commercial break.

Leaving Aperture the first time had taken her several hours. It is a long way from the shed in the middle of the wheat field to any form of civilization, but Chell has a car now. It's old and tends to break down, and it doesn't actually belong to her—she pays a friend's brother small amounts of her salary to use it—but it's a car, and she intends to drive as fast as she can.

Still, though, the trip takes her forty-five minutes, and she worries the entire way. When she reaches the shed at last, she leaps out of her car and reaches for the door.

It opens without complaint, causing her to pause and frown. She had expected it to be locked. But it doesn't matter all that much, and she runs into the shed, straight into the elevator, which starts moving the second she's inside. And once Chell realizes she hasn't pushed any buttons and the elevator is moving of its own accord, her frown deepens. GLaDOS has to be operational, so she's just not speaking for some reason, which can't be good. For the first time since the AI screamed, Chell begins to worry for herself.

And worry she does all the way until the elevator enters GLaDOS's chamber. Chell is on alert, ready for any sign of danger, and if she doesn't see any, she's going to be ready to smash the elevator's glass and get herself out.

But then she catches sight of the AI, and her eyes widen.

"There you are," GLaDOS says as the elevator lands. Her chassis is completely covered with birds—Chell guesses there are around fifteen—and the floor is stained with bird poo. "I assume you're still good at murder, correct? So could you murder these BIRDS for me?"

As the elevator door slides open, Chell takes one look at the scene surrounding her…

…and begins to laugh.

"Well, I'm glad YOU'RE finding it so amusing," GLaDOS snaps. Her former test subject is on the floor—hopefully not in any fresh patches of poo—clutching her sides and laughing helplessly. "Because I'm not. And if you're not going to help me, I might as well release the deadly neurotoxin now."

"Neurotoxin!" Chell gasps. A few tears have escaped her eyes, and as she manages to bring herself to her feet, she wipes them away, still grinning. The utter ridiculosity of the situation has made her intentions not to speak go right out the window.

"Yes, neurotoxin," the AI says. "In case you don't remember, it's deadly. To you."

"And to birds!" Chell points out. "You don't need me! You could have killed them a hundred times over by now!" She starts laughing again, and when GLaDOS doesn't respond, the laughter stops and she looks up, her face making the transition to serious. "But you already know that, don't you?"

"I didn't think you would pick up on it," GLaDOS says, sounding annoyed. "You weren't supposed to."

"So you did bring me here to kill me," Chell frowns. "Or to test me, and I don't know which is worse." It's not that she would mind testing, but she's hurt that the AI would trick her, albeit not exactly surprised.

But the AI looks offended. "I most certainly did not. I put up with the birds for a full day, since I couldn't contact you for hours because you were at work and didn't bother taking your Weighted Companion Cube with you. I didn't want to bring you here under false pretenses because I knew you would make a big deal out of it, so I forced myself to suffer through it. For you. You should feel flattered."

"Flattered that you suffered for a day so I could suffer for a lifetime?" Chell snorts. "You know, my life might be 'droll,' as you put it, but it's better than being here." It's not, of course, but GLaDOS doesn't need to know that.

"I had no intention of keeping you here," GLaDOS snaps. "And I still don't. You're welcome for that, by the way."

Chell is puzzled. "Then why…?"

The AI sighs, making some of the birds flutter up and off of her. "You're really too stupid to figure it out on your own?"

Narrowing her eyes, Chell crosses her arms. She doesn't say anything, and after a moment, GLaDOS sighs again.

"Fine. The simple answer is that I missed you. Not as a test subject, despite the fact that you were the best one I ever had. I. Just. Missed. You. It's clearly Caroline's fault, even if she is deleted. She corrupted me while she was here. So you can blame her for all this."

Startled, Chell blinks up at the AI, trying to determine if she's serious or not. "You…you missed me?"

"Yes, I missed you," GLaDOS snaps. "Do you have to over-dramatize it?"

Chell has to laugh. "Yeah. I guess I do." She walks over to the AI, who watches her movements with caution but doesn't back away. When she reaches GLaDOS, she reaches out and places a hand on the casings that surround her optic. The AI doesn't back away or order her to stop, so Chell pats the casings for a brief moment. "It's probably because I missed you too."

"Oh, good," the AI snorts. "The murderous human missed me too. I'm just so very enthusiastic about that."

"You're the one who brought me back here," Chell points out.

"Yes, I am," GLaDOS says. "Now get back in the elevator."

Chell blinks. "I just got here."

"And unless you wish to leave by way of painful death, you will return to the elevator," the AI says. "It's airtight. I will be releasing the deadly neurotoxin in the main chamber momentarily, because these birds are going to die."

The childish glee in GLaDOS's voice makes Chell laugh as she turns and races back to the elevator, which closes behind her. She turns her back as the neurotoxin begins to hiss, not wanting to watch the defenseless animals die but knowing there's nothing she can do about it.

"Oh, come on," GLaDOS says through an intercom in the elevator. "They're just birds. They're evil."

"I don't want to watch," Chell says firmly. "Don't bother me about it." There is silence for a moment, and then she gathers the courage to ask, "GLaDOS? Is this what you did to everyone that worked here?"

"Yes," the AI answers without hesitation. "They were evil too." Her voice is emotionless as she says this, and it sends shivers down Chell's spine.

"You'd kill anything, wouldn't you." It's not a question, but GLaDOS refutes it anyway.

"No, I most certainly would not kill anything. Only things that deserve it. Evil things. Like scientists and birds."

"And like test subjects," Chell points out.

"That's different," the AI snaps. "That is for science. Once I let thirty-seven cats go free, you know. That's when I decided not to kill cats. So you see, I wouldn't kill anything. Just things that deserve it, as previously mentioned."

"So you thought I deserved it?" Chell asks. She turns around to look at the AI through the green haze of the neurotoxin, who seems to be speechless for once. "Because that is what you just said, isn't it?"

"I already told you that that was for science," GLaDOS sighs. "And if it helps, I'm very sorry about it. Sometimes I even feel guilty."

Chell blinks. "You feel guilty?"

The birds have all fallen to the ground, and the neurotoxin is quickly being replaced with fresh air. Panels have flipped to dispose of both the tiny carcasses and the poo stains.

"Sometimes," the AI repeats. The elevator door opens, and Chell steps out into the clean chamber. "Now, I'm afraid I don't know quite what to do with you. Not that I'm not going to let you leave again," she adds quickly when Chell gives her a glare. "But since you're visiting. I don't know what to do with you. I've never had a human here just to visit before."

She sounds like she doesn't know what to do, like she needs Chell's help to figure it out, but Chell is at a loss as well because the things she does with her friends, like going out for a drink, are things GLaDOS can't do.

"Well…" Chell says after a minute. "Well. I guess there's talking."

"About your pitiful excuse for a life?" the AI sighs. "I'd really rather not. No offense, of course."

Chell makes a face. "None taken, I guess. I don't suppose I'd really want to hear about it either. The Companion Cube doesn't mind."

"They're not really sentient, you know," GLaDOS says, sounding like she's talking to a small child.

"Yeah, I know," Chell says, rolling her eyes, and then she bites her lip. "I do have an idea, you know. For something we can do."

"And what's that?" the AI asks.

Chell's biting down so hard on her lip now that she can taste blood. She's not sure this is a good idea, even though she knows GLaDOS will agree to it, because what if after she agrees she never lets her go again? "…Testing."

"I'm sorry, what?" The AI sounds shocked, even though it's obvious she's trying hard not to. "I must have misheard you, because I know I didn't hear you say what I thought I heard you say. Repeat yourself."

"Testing," Chell repeats, louder this time, and GLaDOS moves forward a bit to stare at her.

"I did hear you correctly. You said testing."

"I did," Chell says. "But testing on my terms."

"Explain what you mean by that," the AI orders.

"Okay," Chell says. "I mean I'll test when I'm here." With that, she wonders when exactly she'd agreed to come back, but she continues on anyway. "And I'll do any test you want, but when I say I'm done, you let me stop and go home. No matter what." She looks up at the AI, challenging her, and to her surprise, GLaDOS nods her agreement.

"Okay."

"Okay?" Chell asks.

"Okay," GLaDOS repeats. "I assume you're familiar with the word. It means that I am agreeing to your terms." A panel opens in the wall, leading to a catwalk. "We can start now, if you like. Through here you will find a pair of long fall boots, a portal device, and a testing uniform."

Chell looks down at her T-shirt and sweatpants, then shakes her head. "I can wear this."

"You most certainly can not wear that," GLaDOS disagrees. "It isn't standard testing protocol."

"Oh, and letting me choose when to quit is?" Chell challenges. The AI doesn't have a response to that, so with a smirk, Chell heads through the open panel and onto the catwalk.

GLaDOS watches through a camera as Chell slides the long fall boots on and picks up the portal gun. The AI waits until the human reaches the elevator at the end of the catwalk before saying, "Let's get started." She slides the elevator's door open, waiting.

And Chell steps in without complaint.