I disclaim.

AN: A few months ago, before the start of season 3, I wrote this speculative little AU fic concerning the question on all our minds: How Mary Knew The Demon. It was a cute little thing, though I say so as shouldn't, and I thought it would sit quietly in a corner of my profile page and maybe collect a review or two every now and then.

Instead the little blighter made such a spectacle of itself, jumping up and down waving at me and tossing plot bunnies around like they were tennis balls, that I now have a 'verse. A full-blown honest-to-God 'verse. Ladies and possibly gentlemen, I give you: the 'Ares and Artemis' series.

Playground

John slowly surfaced out of the darkness of sleep to find that something was wrong. Very wrong. The last thing he remembered of last night was getting back to the motel room somewhere in Colorado he and Deacon were staying in. But none of the motels they'd stopped in over the last two months of their road-trip had ever been this drafty. And none of the beds had been this hard, or lumpy. It felt like he was lying on… wooden planks.

He opened his eyes to the clear blue sky, and jerked upright in shock.

"Holy crap!"

"Sounds about right," a woman's voice said from behind him.

John wasn't sure how he managed to get onto his feet and turn to face her as he was trembling with shock, but he did it. She was about his age, tall for a woman, slender and willowy, with long golden blonde curls caught up in a ponytail and bright green eyes. She was wearing frayed-out jeans and a man's loose shirt over a black t-shirt, and the look on her face was caught somewhere between annoyance and amusement.

And if he weren't so utterly and completely confused by all this, he would have added admiration.

Out of the corner of his eye, he registered that they seemed to be standing on the outskirts of a town that appeared to have been abandoned since around 1820. The sun was out – it was about eleven o'clock in the morning, he guessed – but the streets were muddy. He didn't remember it raining last night.

"So where were you?" she asked, arching an eyebrow at him.

"Where was I?" Not the most eloquent of answers, but he didn't think he could manage anything else. No one who'd just woken up to find they'd teleported themselves in their sleep could've done better.

She rolled her eyes. "Last night," she said. "Where were you?"

When in Rome, John. "Colorado. What about you?"

"Connecticut, at my cousin's place. What's your name?"

John's eyebrows rose. Whoever she was, she was used to being in control of things. Well, too bad. So was he. "What's yours? You seem to know what's going on here."

"You don't seem too freaked out either."

"I'm guessing this is all in my head, right? I'll wake up soon and find I'm in a mental institution somewhere. Probably on my mother's orders."

She burst out laughing. He thought there was a slightly bitter undertone to it.

"No," she said, calming down. "No, this is real. Sorry."

"Sorry I'm not crazy?" If he wasn't, this conversation sure as hell was.

"Yes, actually. You're not going to like this."

"Tell me." He didn't mean to make it sound like an order, but she glared just the same. Oops.

But before he could try to rectify the situation, a guy in flares stumbled round the corner of the hut they were standing in front of and practically jumped out of his skin when he saw them.

"Oh, thank god!" he exclaimed.

"For?" the girl asked sweetly.

The newcomer stared at her in panicked confusion. John thought he looked pretty green in the face. "People!" he said. "I mean, you guys… not alone, you know? Do you know where we are? Is there a way out? Is there a phone? We need to call the cops."

"Call the cops? Why?" John demanded.

Flare-guy pointed back the way he had just come "There's bodies back there… they're torn apart, man. It's awful."

Explained the colouring.

"Show me," the girl commanded, but flare-guy seemed to have finally remembered what his Mommy told him about talking to strangers, because he fixed, first her, and then John, with a very suspicious look.

"Who are you two?" he wanted to know, voice only wavering slightly.

John decided to just go for it. He'd spent enough time around killers lately to be relatively certain this guy wasn't one.

"I'm John Winchester," he said. "Just woke up, so don't even think about asking me anything else. The lady here seems to know a thing or two, however."

Flare-guy nearly fell on his ass trying to get away from her. She turned to John with a glare.

"If I were going to hurt you, you'd be dead already," she told him, and he almost believed her. There was no bravado to her words, just a simple statement of fact. "And yes, I do know a thing or two about this. Mostly how to survive it. But first I need to see those bodies."

John crossed his arms over his chest and tried to hide a grin. The more she talked, the more he liked her. Smart, sassy, no-nonsense, and something about the way she held herself told him she would be, if not actually good in a fight, at least able to defend herself.

"Name, rank, and serial number," was all he said.

She huffed. "Mary Roberts."

He gave her his most charming smile, and made a sweeping gesture in the direction flare-guy had come from. "Thank you. Ladies first."

Was that a smile? Ha. Round one to him.

"I'm Nicholas, by the way," flare-guy said from somewhere behind them. John turned to look at him.

"Well, come on then!"

Somewhere inside him, he knew Mary was right: he should be more freaked out by all this. But it was just too surreal to be true. Like in dreams, there was a small part of his conscious mind that, detached from everything that was happening, was keeping up a running commentary on everything around him, clinically observing the utter nonsense his brain could come up with when supplied with enough alcohol.

But even if he did wake up in a padded cell… if his mind was functioning well enough to come up with a vision like Mary Roberts, he figured he'd be OK eventually.

Nicholas led them to what seemed to be the main street of the town. It curved slightly ahead of them, opening into a small square of sorts beyond which John caught a glimpse of dark and threatening-looking woods. Straight out of a horror movie. The whole place lay in moldy ruins, shutters and doors hanging off hinges, porches collapsed with weeds pushing up between their planks, glass broken in most of the windows.

The further in between the houses they walked, the colder it seemed, sunlight or no. And John couldn't shake the oppressive feeling that he was being watched.

"Cold Oak, Wyoming," Mary said from beside him. He turned to her, surprised, but glad of the distraction.

"The town," she clarified. "It's called Cold Oak – one of the most haunted places on the continent. That's why they abandoned it."

John stared at her. "Haunted? You believe that?"

She tucked a strand of hair behind her right ear and looked at him grimly. "So will you," she promised.

But John's incredulous answer was blown away, along with his unnatural calm, when Nicholas pointed a shaky hand down an alleyway off to their left. A sudden breeze sprang up, bringing with it a familiar smell that would never, could never, leave him: rotting human flesh. He barely glanced at the twisted, mutilated bodies in the alley before turning away with the thunder of gunfire and the buzz of flies on dead bodies and Alex' dying screams in his ears.

Just one thought in his head. This is real. No dream, not even his worst nightmares, could have come up with this. This is real.

Slowly, he became aware he was gripping onto something: a wooden railing, running round the raised porch of a house, forehead resting against it. He was trembling, and he hated it. His hands were clenched so tight he wouldn't have been surprised to find the railing had cut his palms open.

A woman's hand rested on his upper arm, fingers applying gentle pressure. For a moment he thought it was Katie, but when he turned his head, he found himself looking into green eyes, not brown.

Mary Roberts. Right. You teleported, John, remember?

"Nam?" was all she said. He nodded.

"Come and sit down."

She led him over to the steps of the porch whose railing he'd just been abusing, and made him sit down. Then she joined him, her shoulder pressed against his, the warmth of her lending wordless comfort.

"They were torn apart," she said quietly. "I think their hearts were missing… not sure though."

He shuddered. "That's relevant how?" Why did he sound so hoarse?

"Sometimes, they way they died will tell you what did it."

"What kind of animal would do that?"

"No animal. A demon."

"A demon. With a pitchfork?"

The look she gave him was full of pity and sorrow and regret. "No. A demon. A supernatural entity that's pure evil. Kills for fun, wreaks death and destruction upon us puny mortals. Trapped in hell for the most part, but sometimes they get out. That's when the exorcist comes in."

"You're no Catholic priest," was all he could manage. It made her smile, though.

"Even they've started to forget. I'm a hunter. More or less."

"More or less?"

"My uncle wasn't too keen on the idea. Equality of the sexes isn't something he cares much about. So I know the lore, I just… haven't had much practice."

"At hunting demons?"

"Among other things."

She was telling the truth. It was unbelievable, impossible, utterly mad. But she was telling the truth. There was nothing but sincerity, and a touch of concern, in her eyes. She was telling the truth.

"Demons?" Both John and Mary started. They'd forgotten about Nicholas, he'd been so quiet. He was staring at Mary now with wide, terrified eyes and a disbelieving look.

"Yes. Demons," she replied simply. "I know how it sounds. But… well, you saw them."

"This isn't happening," Nicholas whispered. "This can't be happening! I'm supposed to be at home, I have a paper to write, college! My girlfriend… this isn't happening."

"Nicholas…" Mary started out, getting up, but John caught her elbow. "Let him freak," he advised her softly. "Let him get it all out. Then we can work on leaving."

She looked down at him silently, that mix of pity and regret and sorrow back in her eyes. "We're not leaving, Johnny. We're here for a reason. It won't let us just waltz out the front door because we're bored."

"What reason?" he wanted to know, and then, "Johnny?"

Mary smiled. "Suits you."

John decided to ignore that. For now. Ghost towns filled with mutilated bodies were not the ideal setting for a flirtation.

"What reason?" he repeated.

She sighed. "It's a little… look. All I've been able to find is rumours. Stories, half-forgotten legends… I'm not sure how much is true and how much is speculation, you know?"

"Don't you ever just answer a question?"

Again, she smiled. It was rueful and awkward and slightly bitter and always that pitying undertone, like she was thinking, I'm so sorry this is happening to you, like he couldn't take care of himself.

"How old are you?" she asked.

He blinked, but answered. "Twenty-two. Why?"

Mary pushed her hands through her hair, shaking it loose from her ponytail. John got the impression that she did that a lot when she was nervous, or uncertain.

"So am I. So is Nicholas. So were those people in the alley. Anyone else we meet here will have been born in '54, too. That's a part of it. We've been chosen for something."

"I haven't been chosen for anything!" Nicholas cut in, still sounding hysterical. Mary sighed.

"Yes, you have. Let me ask you something: what can you do?"

Nicholas went from hysterical panic to simple, everyday terror in the space of a second. "What – what do you mean?"

"Your ability. Gift. Power. Whatever you call it. Don't be shy, Nicky, we've all got one, or we wouldn't be here. So what is it?"

"What's yours?" he demanded, still uncertain, afraid of their reactions. Apparently he hadn't considered that the question was as good as a confirmation that he did have some kind of ability. John held his breath, waiting for an answer.

Mary smiled sadly. "Persuasion. I can make people do things… but don't worry, it won't work on either of you."

Nicholas kept on staring at her for ages before admitting softly, "I see things. Get visions, premonitions."

"Could come in useful," John tossed in to help himself ignore the voice in his mind that was currently pointing out, if you are crazy, at least now you know you've got company.

"And you?" Mary asked him. He looked away. Crazy. He'd thought it had been a hallucination, but in the face of all that had happened since he'd woken up…

Still, he couldn't really talk about it, the terror he'd felt in those awful minutes, the certainty that he was about to die, the strange hot rush of power that had swept through him like an alien entity in his very blood before…

"I guess… I wasn't sure what it was. In 'Nam, there was this soldier… I threw him into a river. Without even touching him. Saved my life."

Mary nodded. "Telekinesis," she said. "Powerful."

"Powerful?" John repeated. "I've only ever used it the once!"

She raised an eyebrow at him. "You really think that makes a difference?"

He stared at her helplessly.

"What's all this got to do with why we're here?" Nick demanded, sounding slightly calmer. Slightly.

"Everything," Mary replied. "I don't know if our abilities are why we're here, or if we have them because we were meant to come here, and I'm not sure that really matters. What does matter is that we can't use them. Not ever here. You have to remember that, no matter if – no matter what else happens, OK?"

Nick nodded slowly, but John had picked up on the look she'd thrown the boy. There was something about this she didn't want him to know.

The look he got, however, said plain as day, I'll tell you later.

He felt oddly flattered she trusted him. The effortless way she'd taken control of this whole mess, the calm with which she'd faced that alleyway, had impressed him. Most of the girls he knew liked to think of themselves as ladies, sweet and demure and gentle. Mary Roberts, on the other hand, would probably be offended by the title.

Before Nick could ask anything else there came a shout from the other end of the street, echoing dimly between the houses.

"Halloooo? Can anybody hear me?"

"Survivors!" Nick exclaimed and headed off at a run.

"Nick, wait!" Mary shouted after him, but too late. She spun to follow him, but John's hand on her elbow stopped her. Now was as good a time as any.

"Why did you lie to him?"

"He'll be the first," she answered, her voice full of regret. "He's no fighter."

John stared at her, and for the first time that day, real fear twisted his gut. He could see it in her eyes, too.

"No fighter?" he repeated softly, as if to shout, to speak loudly, would make this nightmare even more real.

"We're meant to kill each other, Johnny," she said abruptly, fiercely, as if the words were wrenched out of her, as if she could not keep them inside herself another minute longer, and suddenly he felt sick to his stomach, afraid and alone, a little boy wanting his Dad. "That's what this is. We're meant to kill each other, and the last man standing takes it all. Once we turn our abilities against another human being, once we use them to kill, he's won."

"You guys!" came Nick's yell, and Mary pulled away from John and ran after him. He stayed there for a long moment, staring after her.

We're meant to kill each other…

This was 'Nam, all over again. He took a deep angry breath to steady himself. In, out. In, out.

Get over it, John. If you can survive that, you can survive this. Besides. As far as Mom is concerned, you were supposed to be married to Adela Burton by now, and it hasn't happened. No way is any demon scarier than Caroline Stendahl-Winchester. She's the Antichrist.

He concentrated on that voice, that perpetual sarcastic commentary that always kicked in when he was in situations like this one, a little detached voice of reason that helped him keep his sanity and focus on the job at hand.

Right. Crisis averted.

For now.

He took off after the other two at a run.

At the end of the street, where it petered out into a small square, Nick was bent over a blonde guy slumped against a tall wooden fence. Mary stood back from them, and shot him a warning glance when he joined them.

Whether she was warning him about repeating their conversation or going too near the newcomer was anybody's guess. John decided both, to be on the safe side.

"Girl back there," the newcomer said in a strong Texas accent, gasping for breath, "neck broken." He didn't seem hurt, just out of breath, and terrified.

"It's OK," Nick said, resting a hand on the guy's shoulder comfortingly. "We can sort this out… get out of here. You're not hurt, are you? And what's your name? I'm Nick. Those two are Mary and John."

"Justin," the guy rasped. "No, I'm not hurt. Just… God." He shuddered, and fell silent.

"Neck broken?" Mary murmured. John frowned at her, thinking it through. "If the mutilations – with the hearts missing, if they were demons, then a broken neck…"

Her mouth quirked into a pleased smile. "You catch on quick," she said softly. "Yeah, I think it was a human."

"There's someone else out there, then," John concluded. "We go have a look?" meaning the body.

Mary tilted her head at him. "You be OK?"

He felt a surge of embarrassment over his earlier moment of weakness. "Fine. Just took me by surprise back there."

"Then let's go," she said. "Nick, we'll just check out the body. You gonna come?"

Nick looked up and shook his head. "I'll stay, thanks for the offer." Was that sarcasm? Maybe the kid wasn't such a wet blanket after all. He certainly seemed to have calmed down in the face of Justin's obvious distress.

She wasn't hard to find, poor girl. In the middle of the street, her long hair spread out around her, the bright colours of the patterned dress she wore standing out starkly against the mud. Her head was twisted at such an unnatural angle, there was no question she was dead.

Mary crouched beside her. "I'm so sorry," she whispered, and then froze as her hand brushed against the girl's neck. "John – she's still warm!"

But then – "Justin?"

"Must have been," she answered, and then they both started to run.

"Nick!" John yelled as they reached the corner, round it, there was the fence, "Nick! Oh, god, Nick."

He'd been torn apart, like the others in the alleyway. Heart was missing, John was pretty damn sure.

Mary let out a little whimper of horror from behind him. He heard her slump against the fence and turned in time to catch her up, hug her, before she fell. She clung to him with desperate strength, and he knew then she was just as messed up about this as he was, trembling in his arms, as if the death of someone she'd actually known, however briefly, had opened the floodgates and shattered her self-control.

Just a girl, he thought to himself, holding her close. Just a girl, who's never seen what I have.

Justin was nowhere to be seen.

Mary swallowed her sobs at last and pushed away from John, scrubbing at her tear-stained face.

"We need to settle in somewhere and protect ourselves," she said hoarsely. "There's stuff you'll need to know if we wanna get out of this alive."

"Aren't you worried I'm gonna kill you?" John asked, genuinely curious.

The woman laughed at him. God, she gathered herself quickly. He wondered how she'd come by this strength.

"I could ask you the same thing," she said.

His mouth curved in a bitter smile. "I think I've done enough killing for one lifetime… but that doesn't mean I can't defend myself."

Mary nodded slowly. "Well then. We're more likely to survive if we stick together. He wants us to kill each other, after all."

"You've mentioned a 'he' before," John observed. If that wasn't a hint…

But Mary didn't take it. "Later," she said. "When we're safe."

Sounded like a good plan.

Where Mary found the salt, and the iron poker, John had no idea, but he was more than happy to help her line the doorways and windows in the house they'd chosen to camp out in. Lighting a fire proved impossible: even if they'd had a lighter, there was no dry wood. The place didn't even have furniture to take apart.

"So who's 'he'?" John asked once they were settled in, sitting side-by-side on the floor opposite the door.

Mary sighed. "'It' really. A demon."

"The one who killed those people in the alleyway?"

"Doubt it. I thought about it some, and that was probably some lower-level one… I think Justin was controlling it, that's how Nick died so quickly. Like my power: persuasion over demons."

"And why does he want us dead, exactly?"

"That's what it takes to win. I just can't figure out why he hasn't attacked us yet."

John frowned at the door. "He's waiting to play the winner," he said slowly. "He's thinking only one of us will leave this house alive tomorrow. Doesn't want to fight us both at once."

"Mistake," Mary said. "If we were going to fight, I'd probably leave stronger than either of us are now."

It took a moment before her words sank in. "You'd leave?" John repeated, a bit offended. "I was in the Marines, I'll have you know." She laughed at him, and he caught himself admiring the way the light struck golden glints in her green eyes.

Anyway.

"Back to this winning business," he said, a question, not a statement.

"Yes," Mary agreed. "Listen, I… like I said before, I'm not sure how much of this is speculation. But this whole situation, it's a competition. The Demon wants the winner, the strongest, for something."

Again the clench of fear in his gut. If they killed Justin in self-defense, would that make one of them the winner by default?

"What kind of something?" he asked softly. Any louder and she would have heard the tremor in his voice.

"I'm not sure," Mary said quietly. "Some stories say the winner becomes a demon himself, although the point of that is beyond me. This Demon, it's ancient, one of the most powerful ones. Some claim it set this up to choose a host for itself that he could possess for eternity, and never be driven out of. One hunter even told me 'the Chosen' – that's us – are destined to bring about the end of the world, the destruction of mankind. How, he didn't know."

"The apocalypse?" John muttered. He was pretty sure he looked, and sounded, kinda panicky by this point. "The Apocalypse! Sure, why not? Just stick us all in some abandoned ghost town and wait till we find the giant red lever marked Pull here to end the world!"

Mary burst out laughing again. He thought there was a slightly hysterical note to it.

"Glad I'm entertaining you," John snapped.

"Sorry," she said, still giggling. "It's just… yeah. Look. As long as we don't kill each other, the terms aren't fulfilled, OK? There can't be two winners."

John leaned back against the wall, eyes closed in something near despair. She made it sound so simple, but he knew it wouldn't be. Situations like these did strange things to people's minds. They hadn't known each other for longer than a few hours, and it would be so easy for a thing that had the power to bring them here in the first place to screw with their heads. Add Justin to the mix and they'd be at each other's throats in no time, he was sure.

No, there was only one way out of this mess. They had to leave. Escape the town as fast as possible. And find a way to stop the thing from bringing them back.

The easiest way to do that, he decided, was to remove it from the equation altogether.

"Can't we stop this thing?" he asked. "I mean, isn't there a way to, I don't know, banish it, exorcise it or whatever?"

"No point to an exorcism," Mary told him. "It's too powerful. Wouldn't be long before it crawled back out of Hell."

"Kill it, then," John said.

Mary gave a dry little laugh. "There isn't anything out there that can kill a demon. Oh, there are stories… magic knives, a gun built by Sam Colt, Excalibur of course… but they're just stories. Uncle Ben has never been able to find the slightest proof that any of them are real. The most damage you can do to a demon, apart from an exorcism, is a binding."

"What's a binding?" John asked.

"A spell that binds the demon to a certain object that's magical enough in its own right that the demon's powers are… negated. It's usually made of pure iron, and blessed by some saint or priest."

"A trap, for demons."

"Basically, yeah. But objects like that are extremely hard to come by. Near impossible, in fact – mostly 'cause they're all so old. And we'd need a really powerful one."

"But they do exist, not like the weapons."

"Yeah, they do. Why?"

"Isn't there some way we could find one?"

Mary stared at him. "It's not gonna sit by and watch while we go looking for something to trap it with!"

"I doubt it's gonna kill us until it's got what it wanted from us," John pointed out reasonably. "It needs us. Especially if we make sure Justin's dead before we leave. There won't be anyone else then, will there? Besides, we've got these weird-ass abilities. That oughta help, right?"

"You're serious, aren't you?" Mary said softly. "You don't know jack about my world, and you're actually suggesting…"

John shrugged his shoulders. "You learn something new every day," he said drily. "Besides, I've just resigned my commission, so I don't have anything better to do."

Mary started to smile. "This is gonna take a while," she warned.

"I don't care. I'm not going to spend the rest of my life at the beck and call of some frickin' demon! Something that could do that to Nick, and those other kids… I've just left one war. I won't fight another one on the wrong side."

"Well. I suppose someone needs to look after you."

John laughed. "Thank you."

"You're welcome. Just don't expect to drive my car."

"What model is it?"

"67 Chevy Impala. Uncle Ben gave it to me when I graduated high school."

John's eyes got wide. "67 Impala… marry me?"

Mary tossed her golden curls at him and grinned. "Certainly not. We've only just met."