Disclaimer: Portal and its characters belong to Valve.

Author's Note: This story began life when I was inspired by a piece of art by the lovely Raintalker over on Deviant Art. She told me she had a story behind it that she didn't have time to work on, so I asked if I could do it instead. She agreed and gave me a paragraph of the bare bones of the plot, and this story was born! Although the work is mine, the idea for the basic plot, and the image seen in the cover belong to Raintalker. Everything is used with her permission. If you're a fan of ChellxDoug you should check out her work :) There's a link to the picture that started all this in my profile.

Portal: Sunlight.

Chapter One – The Escape Attempt.

If Chell ever stopped to think about the fact that she was risking her life on a daily basis, she always felt it as a flutter in the pit of her stomach, an almost panicky feeling of vertigo. That was why she chose not to direct her thoughts that way. She was not a woman prone to panic, possessing a level head and a cool temper. On the outside, at least. Inside, she raged and cursed, her anger constantly bubbling under the surface, like lava waiting to erupt at the first sign of a crack. She refused to give them the satisfaction of seeing that part of her. Her anger was her own, and she guarded it closely.

She was nothing here. A commodity, a tool to be used to further the cause of science. If she'd had self-esteem issues, this kind of attitude would have increased them tenfold. Test subjects were treated little better than test equipment: disposable, unworthy of notice, only possessing a bare minimum of intelligence at the very least. She was free to wander around the facility, provided she stuck to the designated areas, but it was like being invisible. Nobody talked to her, nobody even looked at her. She could have walked around naked and she suspected she would have passed through unmolested. Most of the scientists were men, and judging by the pin-up posters on their lockers and the swimsuit calendars, they were typical of the breed. But she wasn't a woman. She was a test subject.

Chell liked to take walks around the facility. It was the only leisure activity she had available to her, and it helped to break up the monotony. It also had the added bonus of letting her make trouble. Nothing major, just little annoyances she could add to the scientists' days. Things like getting in their way, making them move quickly and spill their coffee, rounding corners suddenly and making them drop their paperwork. Things so petty and childish she would never have lowered herself to the level of before. But things were different up here. She had to take what opportunities she could. She refused to protest verbally, and this did the job just as well.

Chell never did anything without a good reason. She knew speaking out would accomplish nothing, so she didn't waste her breath, even though she suspected she would have felt better after a nice, long shouting session. She hadn't uttered a single word since coming to the facility, except whispers in the dead of night, just to make sure her vocal chords still worked.

She scratched tally marks in the ceiling of her room every night. So far they hadn't been discovered. She was certain she would face disciplinary action when they were. (And it was 'when', not 'if'. She was certain of that too.) She wasn't looking forward to that, but the scratches were worth it. Counting the days gave her perspective. She'd seen her fellow test subjects break. Outwardly they were the same, but inside they'd given up. They no longer cared if they lived or died, drifting through an endless cycle of test running and existing. It was existing because it sure as hell wasn't living. Their faces were blank, pale, lifeless. The bright spark in their eyes had long since faded. Chell would have found it sad if it didn't make her so angry. She couldn't imagine just giving up and letting things happen to her. She was in charge of her own life, even though being at the facility was a huge setback to her freedom. She'd been there 110 days so far, and she didn't feel ready to break any time soon.

The scientists seemed determined to do it, though. She was locked in a constant battle with them, unable to figure out why they were trying to break her down. It had her worried, not that she'd ever show it. She was a methodical person, relying on logic to see her through, and this didn't make sense. She didn't like things she couldn't figure out. If she couldn't figure it out, she couldn't decide how to solve the problem. Problem solving was why she was there in the first place. It was why all of them were there.

The worst part was, she'd volunteered. Not for this. She'd never have imagined it could be this bad. But she'd volunteered to test devices for the company. She'd done one or two tests at the main facility, tests that seemed casual by comparison. She'd tested the Aperture Science Handheld Portal Device, dubbed the portal gun by those with less time to spend on syllables. She'd been politely congratulated on her compliance and ability, then rewarded with a sedative she hadn't consented to. When she'd woken up, she'd found herself in a capsule bedroom, containing a slim mattress and a single pillow. The ceiling had been a mere three feet above her, the walls close enough together that she could scrape her elbows on them. Opening the door had revealed a nasty drop down. Her room, if it even deserved the word, was the sixteenth row up in a bank of identical doors. Woozy and disoriented, she'd made her way down the tiny ladder beside her pod. There was nothing but a corridor below, and its polished, slate grey surface had been surprisingly cold under her bare feet. It was a journey that she now made on a daily basis.

The real shock had come when she'd reached the window at the end of the corridor. There had been no windows where she'd been at Aperture. The majority of it was underground. So it had been with some anticipation that she'd headed towards this one. When she looked out at what she'd assumed to be the night sky, her jaw had dropped. There was a ball of swirling blue, green and white where the moon should have been. The landscape she could see outside was rocky and pitted, grey and monochrome. In the distance, she could make out a tiny flag, a proud display of the stars and stripes.

She'd known straight away exactly where she was, but it had seemed so ridiculous to admit that she was on the moon, even in her own head, that she hadn't bothered. She was immediately furious, knowing they had no right to abduct her this way, and knowing that there was nothing she could do about it. She'd joined a group of fifty test subjects 'specially handpicked' to take part in Aperture Science's new and exciting lunar project. Or so the introductory pre-recorded message had told her. Within hours she'd found herself garbed in a skin-tight white and orange jumpsuit and long fall boots, a new kind of portal device attached to her right wrist. It hadn't taken her long to get to grips with it, or the zero gravity test chambers they sent her to. She'd been solving their tests ever since.

The number of test subjects had dwindled down to thirty-three since she'd been there, and as yet they hadn't been replaced. She'd observed that a supply shuttle came once every three weeks, and that some of the scientists looked as longingly at it as she did. Not speaking gave her the opportunity to watch, and she noticed everything. There were only a handful of scientists there that seemed to genuinely want to be there. Everyone else looked miserable, but dedicated. She knew just by looking at them that they wouldn't help her escape, even to get out of there themselves. She'd vowed to do it on her own. And today, she would fulfil that vow.

She wasn't testing, which meant she was walking. She was drifting perilously close to an area she wasn't authorised to be in: the corridor that led to the unloading bay for the supplies the shuttle brought. As plans went, it wasn't as good as she would have liked. There were far too many things that could go wrong. But it was literally the only option she had. They'd been unloading for fifteen minutes now, which meant that she had almost two minutes before the station closed the airlock.

She wandered closer and took a look around. There were no scientists looking her way, and the management rails were free of cores. That was enough for Chell. She bolted. She swiped her stolen I.D. card through the reader and slipped through the door, letting it slide softly closed behind her. She pelted down the corridor, her bare feet silent against the cold, hard floor. She skidded to a halt before she could draw attention to herself, peering into the unloading bay. She was going to have to make a run for it. There was no one between her and the airlock. At the back of her mind, a cynical strand of thought wondered why her path was so clear. But she didn't have time to worry about it. She just ran.

She was across the unloading bay in seconds, frantically pressing the panel to open the airlock door. She darted inside and hit the panel for the second door, the only remaining barrier between her and the shuttle. It flashed a stern red light at her and refused to open. Wariness seeping in, Chell hurried back the way she'd come. The door into the unloading bay was now locked too. She was trapped in the airlock. The shuttle, she could now see, was leaving. She bit her lip, refusing to give in to the approaching panic.

"That wasn't a wise course of action, 1498," said a muffled voice.

Chell glanced up to see a group of three scientists clustered around the porthole window in the door. She clenched her fists by her sides, awaiting the force of their displeasure. It always angered her to be addressed by a reference number rather than her name, but of course, they'd never called her anything else.

"Do you have any idea how much trouble you cause?" the head scientist - she thought his name was Peter - asked rhetorically, his tone sharp and commanding.

She resisted the urge to nod. It would annoy him, and that was a satisfying thought, but at this stage she knew it would be unwise to push her luck.

"I hope you can appreciate that I can eliminate all my problems with the flick of a switch," he went on. "The switch that operates that door, to be precise."

Chell didn't need to look behind her to know that he meant the door out to the vastness of space, and not the one that would let her back in to the facility.

"Uh, sir?" said the man at the back, clearing his throat. "1498 is my test subject. The choice to dismiss her should be mine to make."

Chell almost lost her grip on her silence at his use of the word 'dismiss'. It was insensitive and cold, and what was worse, she suspected he didn't even fully realise that fact.

"In normal circumstances I'd agree, Mr. Rattmann, but this one..." He waved a hand at Chell in a way that made her feel like an insect in a specimen jar. "Are you sure she's not more trouble than she's worth?"

"I'd say her results speak for themselves, sir. I've never..." her supervising scientist trailed off, glancing up and meeting her eyes. She stared at him blankly, hoping to make him awkward, to gain back what power she could. He looked away after a few scant seconds, turning back towards Peter. "Are you sure you want to have this conversation in front of the subject, sir?"

"Sure. What's the problem? Who's she going to tell?" Peter said, throwing back his head as he laughed, giving Chell an unwanted view of his poor dental work.

She indulged in a brief fantasy of shoving the portal gun down his throat.

"Carry on, Mr. Rattmann."

Her supervisor, one Douglas 'Doug' Rattmann, glanced at her once again before continuing. She saw his mismatched eyes narrow a fraction as he took in her expression.

"I've never seen a test subject like her, sir. Her results aren't at all what I was expecting. I'd like to take the project as far as I can."

Peter shrugged nonchalantly. "Well, it's up to you. I can't deny that you have a point, but bear in mind, I will start holding you accountable for her actions if she steps out of line again."

"I understand, sir."

"Whose I.D. did she steal anyway?"

The third scientist, a nervous-looking man who seemed to have fallen into the role of Peter's personal assistant, consulted his clipboard. "Um...Victoria's, sir. She reported it missing about an hour ago."

"Send her to my office, will you? We can't have test subjects running around stealing I.D. cards. It's bad enough we have to have them roaming the halls."

The approaching sound of running footsteps attracted their attention, and Peter and his lackey turned to look. Rattmann, again, looked at Chell, his expression thoughtful as he studied her.

The knowledge that she was trouble had made her feel reckless, and she held up Victoria's I.D., letting it swing gently on its lanyard. Her lips curled up in a wry, slightly smug smile.

His eyes widened and he glanced at Peter, presumably to check he was still distracted. Then he made a small but perfectly clear gesture indicating that she should stop rubbing the theft in his face.

"Sir," a panting voice from outside was saying, "I couldn't get you on the comm. Can you come down to catering? They're saying the Atmospheric Monitoring Sphere is malfunctioning. It's stuck on its rail by the window and it won't stop talking about being in space. They say it's very distracting to their work."

"Hmph," Peter spat, sounding more than a little unimpressed. "What do they have to be distracted from? All they do is stand around heating up rations!"

"Even still, sir, we should get the Atmospheric Monitoring Sphere working if there's a problem."

"Yes, yes, I'm on my way." Peter turned back to Rattmann, his body language already indicating an air of dismissal. "Do what you have to do, Doug. She's your responsibility."

With that, Peter and his nervous assistant departed, leaving Chell alone with her supervisor without even a parting glance.

He let out a weary sigh, his breath briefly fogging up the glass of the tiny window. Chell, who was unsympathetic with him at the best of times, did not care two straws for his obvious tiredness. She had been threatened with being ejected into space, and he was the one acting as if his day was going badly! She slammed her palm against the glass, feeling a small ripple of satisfaction as he jumped.

"Hey, none of that," he scolded. "Didn't you hear the part where he said it was okay for me to open that door?"

She raised her eyebrows, almost in challenge. She had been testing for this man for nearly all of her 110 days. She didn't know him well, but she didn't think he was the type who would send her to her death without a solid reason. He was a little callous, a little self-seeking, a little introverted, but he wasn't a monster.

He ran an ink-stained hand through his untidy black hair, causing it to stick up in unruly spikes, giving him a slightly unstable look. She'd heard whispers that he was 'the crazy one', whatever that meant. She didn't know, and she certainly didn't care. The whole lot of them were crazy from her perspective.

She began spinning Victoria's I.D., winding and unwinding the lanyard around her index finger as she changed direction.

"Look," Rattmann began, his voice betraying a touch of jaded dullness, "you're causing me a lot of headaches." He glanced up, watching her spinning. "And that isn't helping."

She shrugged. She knew she was being petulant, but the day's events hadn't put her in a cooperative mood.

"Do you want to get yourself killed?" he asked, leaning a little closer to the glass. "I don't believe you do. Not when you're the only test subject who..." He trailed off, huffing gently. "Well, you already know that, don't you? You're not stupid. They think you are, you know. They think you haven't given up because you don't understand. They think because you don't speak you've got some kind of brain damage."

Chell didn't care what they thought of her. In fact, she preferred to be underestimated. But she could tell from the penetrating look he was giving her that he wasn't fooled. She met his gaze steadily. Whatever her opinion of the man, she had always found those mismatched eyes oddly fascinating. They were a clear, light shade of blue, with one pupil much larger than the other. Set against the black of his hair and the paleness of his skin, they were almost the only bit of colour in his face.

"I don't know what your problem is," he went on. It was a simple statement of fact, not rudeness, which caused her to quirk an eyebrow in mild surprise. "You definitely speak English, I can see you understand what I'm saying. Can you...just not talk? And your behaviour is some kind of outlet? Help me out here, I'm trying to understand."

That wasn't what she'd been expecting, and she wondered why he was trying to understand.

"Well how else am I supposed to figure you out?" he added, and her eyes widened as she realised how easily he'd read her expression. "You're surprised. I'm not stupid either, you know. Surely you can appreciate how puzzling it is to have someone volunteer to be a test subject and then act the way you act when asked to test. Can't you see why I wonder about you?"

Chell eyed him apprehensively, unsure whether he was ignorant of the way she'd been brought there, or if he was simply lacking in empathy.

"If you just stop this, we can complete the tests and we can both leave. Why make it harder for yourself?"

She wondered if he had forgotten that some of the tests, especially now she was getting into the more advanced ones, were dangerous to the point of being lethal.

"I know the tests are difficult," Rattmann said, causing her to narrow her eyes, daring him to patronise her. "But you signed up to beat them, didn't you? You're taking part in ground-breaking science here. Only a handful of people can say they've tested revolutionary technology, on the moon, no less."

Chell turned away, biting her tongue. She clenched her fist, wishing she could swing it at him and break the rose-tinted glasses he was obviously looking through. Taking part in ground-breaking science? The part of her that had once held an interest in science had long since died. Her life consisted of being forced to sleep in a pod she could barely sit up in, being given nutritional injections in the place of real food, having nothing to do except wander aimlessly around the facility, being assigned fifteen minutes of shower time a week, (which she could divide up as she saw fit), and do all of it in temperatures that she was certain were below the legal limit for working conditions. And when she was not doing that, she was dodging laser beams at zero gravity, doing her utmost not to get killed, because this life was still better than no life at all.

Part of her wished she could tell him all of that. But her silence was effective, and gave her some measure of control over her existence. Aperture had control over everything else, but her voice was hers to use as she chose. And she chose not to.

"Look, just…can you…look at me? Please? 1498?"

She stared fixedly at a mark on the wall, and heard him sigh heavily.

"Okay, fine. Just listen. Can you please not do anything like this again? There will be repercussions. I could get fired, you know. And you…well, I don't even know. But you can bet it won't be good."

Chell gave a sigh of her own, reluctantly agreeing with him. She wouldn't get off this easily next time.

"Obviously it's up to you. You'll do what you want anyway, no doubt. But bear in mind that I'm asking, 1498. I could just bark orders at you, but I get the feeling you wouldn't respond well to that."

Against her better judgement, she turned her head and studied him. He was watching her with open curiosity. The artificial light threw his features into sharp relief, accentuating the shadows under his eyes, the acute angles of his cheekbones and prominent nose. He was sporting a few days' worth of stubble. Razors, she guessed, were still packed away among the new supplies.

In the glint of her eyes, she gave him just one instruction for him to pick up on if he could: Use my name.

"I can't let you out unless you agree to cooperate."

Chell glanced down at the lanyard coiled up in her palm. In the right hands, it could be a weapon. It was designed to go around necks, after all. But was she really that kind of person? It wouldn't bring back the shuttle. And Rattmann didn't deserve to be strangled just for being a bit of an asshole. He wasn't the first one she'd had to deal with and she was sure he wouldn't be the last.

Thoroughly disliking the cold trickle of defeat that settled in her stomach, she met his gaze once more and nodded.

"Okay. Good."

He punched his security code into the panel and the light changed to green. Chell seized the handle and darted out, relieved to be another step away from certain death. She hadn't let herself think about how disconcerting that feeling was. In the tests, there were always things she could do to prevent herself from getting killed. Being trapped in an airlock snatched that control away from her.

Feeling Rattmann's gaze upon her, she forced herself to calm down. She didn't want to give him any insights into what scared her, afraid that they would somehow find their way into the tests. But judging by the look on his face, it was too late to fool him.

"You didn't like that, huh?"

She shot him a contemptuous glance. It was a completely absurd thing to say.

He seemingly chose to ignore it. "I'm going to need that back," he stated flatly, pointing at the I.D. card.

She handed it over. It had served its purpose. His own I.D. hung from a clip on the breast pocket of his lab coat. The clips provided a much bigger stealing challenge than the lanyards. That was why she hadn't taken his card, even though she'd had chances.

She glared at him, feeling her lips purse in a sullen pout, wishing she could hate him, but somehow not mustering enough strength for it. On closer inspection, she had to rethink her earlier assessment of him. He didn't just look tired, he looked exhausted. A curious part of her wondered why, and briefly considered what sort of pressure he had from his superiors that would make him push her so hard. She still wasn't convinced he was a cruel man, even taking into account everything she'd been through so far.

He escorted her back through the unloading bay and down the corridor towards the door into the main body of the facility. She halted outside it, waiting for him to swipe his card. He hesitated, watching her, apparently thinking of something he intended to say.

Chell leaned back against the wall. Not only did it demonstrate her lack of caring, but it also gave her a little more room. The corridor was narrow, and he was only half a head taller than she was, which almost put them on an equal eye level. It was unsettling.

"They will dispose of you if you cause too much trouble, you know that, right?"

She nodded. She never doubted Aperture's ability to dispose of test subjects as it wished.

"I mean it."

She sent him a look that clearly stated, 'Well, duh.'

"Okay, okay, I'm just saying. I just want to make sure you understand these are not idle threats." He pinched the bridge of his nose, briefly closing his eyes. "You may not believe it, but I actually don't want you to die. Okay? There's no need to encourage that kind of waste of life."

She observed him doubtfully, pondering the truth of his words. They were easily spoken, matter-of-factly. There was very little emotion behind them.

Shaking his head slightly, he slid the card through the reader and opened the door. Chell stepped through without waiting, and he followed.

"You're scheduled for a round of tests in three hours," he told her. "I'll see you then."

He headed away from her, in the direction of the scientists' private quarters. Chell watched him go with narrowed eyes. She didn't know what it was like there, of course, but in her mind he and the others were enjoying their own luxury suites with king sized beds, hot tub baths, and bookshelves. It was unlikely, she knew that. Aperture treated its staff well, within the limits of the law, but not to an extreme extent. But time and boredom had made her bitter.

Still feeling the discomfort of defeat, she turned away and started walking, with nothing to do but pass the time.

A/N: Updates will be weekly. Probably. That's the plan anyway. This story is finished, so there's no chance of abandonment :)

Reviews much appreciated :)