Warnings: Swearing and vague references to alchol, sex, and death. Mostly mild, but later chapters will include more mature and explicit content. Expect things to get dark. Specific warnings will be posted for each individual chapter. No slash!

Timeline(s): Deliberately unspecified, but roughly 3-4 years after The Avengers movie and sometime after the (still unaired) season 10 of Supernatural.

Disclaimer: I do not own The Avengers or Supernatural. In fact, the only thing I lay claim to as my own is any and all mistakes since I have no beta.

Author's Note: Although everything that has already happened in the Marvel Cinematic Universe/Supernatural is canon, I am playing loose and fast with both universes going forward, which includes shaking up and adding to the Avenger rooster (borrowing heavily from the comics) and referencing events that have not happened onscreen. I have also not incorporated what little is known about the upcoming 2015 Avengers movie, since that just seemed like borrowing trouble. So there.

"Wer mit Ungeheuern kämpft, mag zusehn,

dass er nicht dabei zum Ungeheuer wird.

Und wenn du lange in einen Abgrund blickst,

blickt der Abgrund auch in dich hinein."

Translated:

"He who fights with monsters should look to it

that he himself does not become a monster.

And when you gaze long into an abyss

the abyss also gazes into you."

- Friedrich William Nietsche (1844-1900)

Chapter 1 - The Asset

"I still don't get why I had to come," Tony bitched, his petulant tone combining with his suit's characteristic metallic pitch to produce a rather odd effect."In case you hadn't noticed, I'm an extremely busy guy what with being a superhero, saving the world on a regular basis, inventing nifty stuff, and going to awesome parties. Honestly it's exhausting. Not that I'm complaining, mind you. I'm just saying..." Tony's ramblings were cut short by the arctic look Hawkeye sent his way even as the sniper's focus remained firmly on their surroundings, a desert eagle clutched comfortably in his right hand.

Ignoring the almost visible waves of hyper vigilance that were rolling off his team member, Tony shrugged and continued his tirade: "... that if this guy is as paranoid as you say, why couldn't you have brought Captain Goody-Two-Shoe instead? A handshake and that 'I am an American hero' crap Cap does and I guarantee that your mystery guy will be first in line to join the Avengers' fan club. And yes, before you ask, we do have an official fan club. Not that I've spent any time researching it of course, and I definitely don't know that the president is a really, really hot chick named Stacy who loves yoga, kittens, and for some reason heavy metal rock, which in my opinion just makes her exponentially more hot."

"Stark."

"Yes?"

"Shut the fuck up."

Looking at the team's resident sniper and certified sociopath (he had the S.H.I.E.L.D. psych profiles to back up the claim), Tony instantly swallowed his instinctive snarky reply.

Hawkeye's face had taken on that expression. The expression that he had worn for months after New York and which quite frankly freaked Tony the hell out. Barton's eyes were completely dead and his face had gone carefully blank except for the slightest hint of a smirk twisting his lips; half a challenge and half a promise of violence and a not-so-swift death to anyone who fucked with him.

It was, Tony had realized after the first few weeks of sharing a living space with the man, the sniper's fall-back position when he felt stressed, threatened or uncertain. And it came complete with lethal startle responses and a sadistic streak that had made even the Widow blanch on occasion.

It was also shit-your-pants terrifying when it was focused directly on you. Especially if you had seen firsthand the kind of carnage a pissed off Hawkeye was capable of.

Waiting half a beat to see if his message had been received, Barton nodded and his cold smirk deepened for a second before he took the lead again, completely ignoring his garish gold and hotrod-red colored companion.

"Asshole," Tony mouthed mutely behind the safety of his helmet before picking up the pace.

What was his deal anyway? Sure Barton was a stone cold killer with some serious mental issues, and yeah okay, so his friend/comrade/lover/fuck-buddy or whatever the hell Mockingbird had been to him, had died a pretty horrible death three months ago. But Tony was definitely not going to think about that right now because then he would start to remember other things, such as the sanctimonious garbage Cap had spewed at her memorial or Fury's callous spiel about tactical decisions and acceptable losses, and just thinking about it made his teeth itch and the permanent coil of burning anger in the pit of his stomach roil.

So no, he was not going to think about Bobbi or the fucked up mess her death had left the Avengers.

Anyway, Barton's issues had issues. According to his S.H.I.E.L.D. files, Loki's brainwashing had only been the rotten cherry on top of a truly shitty sundae that had been his life up to that point. Tony was actually a little impressed that the guy was as mentally stable as he was. On a good day he could even be pleasant company with a surprisingly funny, if somewhat twisted, sense of humor and a clearly unhealthy obsession with blowing shit up. A vice Tony himself shared. This had lead to some quality bonding time before Pepper (now also categorized as a toxic mental subject which was studiously avoided) had put her foot down in concern over the continued structural integrity of the tower.

Hawkeye was a teammate, someone he trusted his life with on a regular basis. And yes, on a good day Tony would even categorize Clint as a friend; albeit a scary, antisocial, and sometime slightly psychotic friend. Today, however, was obviously not a good day.

Tony sighed. He had really hoped they'd moved past this part of the teambuilding process because quite frankly the fact that he was more often than not thrust into the role of the responsible adult, the peacekeeper, the one who, for Christ sake, 'played well with others'; well, that sentence in itself pretty much just summed up how incredibly screwed up the rest of the team's social skills were.

Fuck it! He sucked at walking on eggshells anyway, and it was not like Barton was actually gonna shoot him. And even if he did, there really wasn't much damage a bullet could do to his titanium enforced armor, even if Hawkeye was the greatest marksman in the world and, standing a mere five feet away, could probably single out a particular alloy molecule and hit it.

"You seem unusually grouchy there, Katniss." Ah well, in for a penny in for a pound. "Did Granny Russia kick you out of her bed with blue balls this morning?"

Tony could see Hawkeye's shoulders tense almost imperceptively at his first barb. The archer's smile, when he turned around and stared at Iron Man, was downright nasty. But his eyes had lost their dead expression and instead sparkled with sudden glee, which Tony decided should count as a win in the grand scheme of things.

"You do realize that Natasha can hear you over the comms, seeing as she's running this op, right?"

Oh shit. Fuck. Shit. Holy shitfuck. He was dead. Like literally dead. Tony felt his guts turn to water and he swallowed thickly. The Black Widow's real age had only recently been revealed to the team and while she was still smoking hot, like ridiculously supermodel going on goddess hot, the knowledge that she was over 80 years old had really put a crimp in his favorite sexual fantasies starring the red-haired assassin. It didn't seem to bother Clint though, if the traffic around Natasha's door, monitored dutifully by Jarvis' hallway cameras, were anything to go by. Not that he had been keeping tabs of course, since that would be creepy and stalkerish.

"I'll buy you a new Lamborghini if you don't kill me when we get back," he offered up as a Hail Mary to the suddenly very ominous silence on the comm link (static was for inferior engineers).

Holding his breath he quickly did a mental tally of the pros and cons of living, sleeping, and shitting in the suit 24/7 vs. finding a nice isolated cave somewhere to live in for the next couple of years.

"Make it two new Harley Davidsons and you've got yourself a deal." Came the blessedly cool and, as always, calm voice of Romanoff over the comm. "Oh, and Tony. If you ever call me that again, I will cut out your tongue and give it to Pepper in a nice box with a big pink bow," she threatened pleasantly and with completely sincerity.

"Deal!" He accepted gratefully, ignoring the bit about she-who-shall-not-be-named. And also carefully ignoring the little voice at the back of his mind pointing out that it probably wasn't normal to be threatened with actual death and/or bodily harm by your friends and colleagues on a daily basis.

Hawkeye, the bastard, had smirked the whole way through the conversation. His eyes had never stopped sweeping for threats though, nor had his finger slipped so much as a millimeter from the perfect pressure point of the trigger.

Still feeling the cold sweat of his near miss crawling down his neck, Tony couldn't help but feel deeply resentful of the whole situation. He hadn't asked to be out here saddled with a pissy hawk and a scary spider in his ear, in fact he had vehemently opposed this assignment. The hangover from, let's be honest not so much last night as this morning, was steadily making its presence known in the slightly stale air of the suit and now that he was thinking about it the cut on his right hand was starting to itch annoyingly without any chance of relief (a little known fact was that random itches were the bane of his existence as Iron Man).

"Who the hell is this guy I'm slogging through the ass end of nowhere to meet anyway?" He asked grumpily.

"An important asset," came the Widow's smooth answer. She had apparently decided to join the conversation now that the radio silence had already been broken. Either that or she was attempting to cushion Hawkeye's last fraying nerve by relieving him of the need to engage with Tony.

"Oh well, if it's an important asset." Tony was rather proud of the amount of sarcasm he'd managed to infuse into the sentence.

He could clearly hear Natasha's sigh over the comms. "He's an expert on the occult. Supposedly one of the best, even though we have next to no intel on him. And what we do have is..." He heard a slight hesitation in her voice, as if she was carefully choosing her next words, "... even if the rumors have been wildly exaggerated... worrying."

Which explained why Hawkeye was in DEFCON 1 mode. Apart from hating going in blind to a meet, the mere mention of magic or the occult usually meant hours spent on the range shooting things with more than a little prejudice - and if he was out on a mission, then God help the poor schmuck that had the misfortune of being his target. But then again, after Loki who could really blame the guy?

Still. A year and a half ago, a disgraced former apprentice of Strange had decided to muck around with dark forces far beyond her power in a regrettable fit of megalomania. The result had been a swirling vortex of fire and brimstone raining down destruction on a small sleepy town in Nebraska. As soon as the kill order had gone out (and the non-killing members of the Avengers had removed themselves from the field) Hawkeye had taken her down. Hard. To this day Tony still got a little nauseous when he saw shish kebab.

"I still don't see why I had to be the one to come out here," Tony returned to his original complaint. "Why can't Fury's pet agents handle this little meet 'n' greet. I mean we're the A-team. Literally. Huh, there must be some sort of copyright infringement thingy right there. I should check into that when we get back."

"Because he would only meet with members of the Avengers," came the dry response, ignoring the last rambling part, before continuing: "'Said he wanted to meet someone he could recognize from the media. And he asked specifically for you. Which you would already know if you hadn't been more or less comatose during the briefing." The Widow's voice managed to convey cool disapproval while being completely neutral at the same time, which all things considered was a rather impressive trick.

Tony didn't raise to the bait. He also didn't need to ask why Natasha, their best manipulator and therefore negotiator, wasn't out here instead of a jumpy and slightly homicidal Hawkeye. Although medical had declared her almost completely healed from the whole gigantic cobra and snake venom poisoning ordeal, 95% was still not the same as a 100%, and there was no way in hell Clint would allow his partner to go into a potentially dangerous situation playing wounded. Bobbi, for obvious reasons was also out, and since this was more of a S.H.I.E.L.D. operation than Avenger business, at least one agent had to be present. Pym, the smug bastard, was currently sitting comfortably in the jet (nose practically glued to a Stark pad) acting as potential backup should things go sideways.

Cursing whatever whim had made the asset (or just ass, ha!) request him specifically for this date, Tony petulantly trampled on the small twigs and medium branches that lined the path they were currently following. He felt a slight rush of satisfaction from this minor act of destruction right up until the moment Hawkeye turned around and gave him a murderous look for making a racket and giving away their position.

Some days Tony really hated his life.

Iron Man had initially flown them the first couple of miles from where the jet had set down in a barren field. Hawkeye had quickly ordered them down though, and they had now been walking for ten agonizing minutes through a mostly wooded area (side note: the suit had notbeen designed for land based locomotion ).

Tony's earlier comment about this being the ass end of nowhere was, if not particularly kind, not completely unfounded either. During the last half hour of the flight on the jet, the only thing the landscape had been able to offer was a few scattered small towns, mostly of the one main street variety, connected by long stretches of highway, lots and lots of fields as well as the occasional dark green splotch of a forest or black twisty bends of a river, back-dropped by an unassuming mountain range in the horizon.

Despite the general lack of landmarks, Hawkeye appeared to know exactly where they were going. Tony hadn't bothered to find out and wasn't even completely sure which part of the country they were in, having slept through most of the two and half hour flight. The archer finally slowed down when they cleared the last of the small patch of trees they had been walking through and took stock of the decrepit barn, sagging and groaning under its own weight, that now faced them. Parked next to the structure was a shiny black muscle car; a classic Chevy Impala, Tony noted absentmindedly, and in amazing condition too despite the clear mileage on the machine. The main barn port stood slightly agape, as if to invite them in.

Tony was not impressed.

"Seriously?" He groaned. "What is this, a hoedown party for hillbillies? And I didn't even bring my dancing shoes."

"Hawkeye, report," Romanoff's voice cut through Tony's complaining.

"Meeting point identified. The car is here as described. No visual on the asset so far." Hawkeye answered in a clipped voice.

"Acknowledged. Proceed as planned."

"Copy."