I thought I'd left for good, and then this recent episode propelled me to write.

This is a tag to episode 207, "Who Do You Trust?" Spoilers up until that episode. SPOILER WARNING STARTING NOW.

For those who need a quick refresh, or want to read this without having seen the episode, 207 was when Fury revealed to Stark that he'd been hiding with Mockingbird and Widow after discovering that Viper was a Skrull. They suspected Hawkeye, since Viper stopped the Baron from killing him back on Hydra Island. Tony went back to the mansion with this news and chaos ensued. This is a tag to that episode and will therefore be Alternate Universe once episode 208 is aired.

Until then, enjoy!

Tony Stark had experienced a lot of different kinds of pain. He'd been shot at, blown up, smashed, punched, kicked, frozen, blasted, burnt, and electrocuted, to name a few. But he would have traded all of those in a heartbeat for the sick feeling that had settled in his stomach.

Skrulls. It was all down to Skrulls.

His team - which had finally, yes, after all their mishaps, become a real team - broke under a few minutes of suspicion. No one could be trusted.

Being something of a genius (if he did say so himself), Tony was smart enough to realize that this was probably all part of the Skrulls' plan, or at the very least their plan "B" after their presence on Earth was revealed. What better way to disrupt your enemies than destroy any cooperation between them?

But he had no way to counter. He had scanned the occupants of the mansion with every technique his suit could employ and seen nothing that would hint to the identity of the Skrull. Pepper could be a Skrull for all he knew of them. So he was trapped here, by himself, scribbling and crossing out bizarre ideas and trying to ignore his mounting frustration.

"You have a call," Jarvis' voice interrupted his thoughts with its smooth baritone.

"Jarvis, I told you, block everyone," Tony growled.

"This is the 27th attempted call from Mr. Barton. He says he would continue to call until you hear his first message."

Tony sighed. Skrull or not, Clint could be as irritating as a bed bug when he put his mind to it. At least pretending to listen might get him to go away for a while. "Fine, tell him to stop calling and play the tape."

Surprisingly, there was no visual: the call had come over a standard phone instead of one of Tony's higher-end communicated gadgets.

"Tony." Clint's voice was sharp and surprisingly devoid of the anger Tony had expected. "I know right now you feel like you can't trust anyone, least of all me. But I need you to listen just one more time. I'm going to be at the pizza place where we met before, and I'm coming unarmed. I don't care if you show up in your suit, just meet me there and listen to what I have to say."

For a moment, Tony regretted having refused to take Clint's calls. It would have been so much more satisfying to reply to that message verbally, instantly, yelling down the line for Hawkeye to leave him alone.

On the other hand, Tony WAS stuck for inspiration. If this really was some Skrull-copy of the archer trying to protest his innocence, maybe he would make a mistake. It was worth a shot.

Thirty minutes later Tony walked into the pizza parlor. He decided against wearing the Iron Man armor, though he could have it on in two minutes if necessary. Strangely enough, there was no sign of Barton.

Tensed for an ambush or worse, Tony jumped slightly when a waitress tapped him on the arm.

"Sorry, sir," she apologized. "You're Tony Stark, right?"

"No, I'm Stony Tark," Tony grumbled, his temper still short from recent events. Fortunately the young woman interpreted that as a joke.

She held out a piece of paper, white but covered in a black scrawl. "I'm supposed to give you this. And say thank you for coming. I don't know what that means -" she seemed about to express her own opinion on the matter when a call from a table, impatient for service, drew her away.

Alone, Tony moved out of the doorway of the restaurant so he could examine the paper.

Stark -
I know you at least have enough skills to manage a simple palm. When you're done reading, tear this in half. Palm the top half. Rip or crumple the bottom half and throw it away, then storm out of here back to your building. You once showed me a weak point in your security. Meet you there.
Apologies for the cloak and dagger crap.

That took only the top fourth of the sheet. Underneath it began the kind of drivel Tony had been expecting, an angry, bitter rant defending Clint's innocence and condemning Tony's actions.

Tony's first reaction was to shove the whole letter right down Clint's throat, but as his fingers crumpled the paper in anger, he remembered that Clint had been a trained spy and assassin for SHIELD; no doubt this wasn't the first time he'd concocted strategies to shake tails and avoid surveillance. Since anyone could be a Skrull, it made sense that Clint would only want to talk openly if he knew they were alone.

Okay, Tony thought. He'd bite. But if this was a wild goose chase, he was going to punch Clint right in the archer's smug face.

The "weak point" Clint had mentioned was a small room in the Stark Tower.

As the elevator climbed, Tony thought back only a few months ago to when Clint had come to him asking for a private conversation. Barton had wanted to discuss the technology of his assortment of trick arrows and insisted they talk somewhere with no chance of being overheard.

It's a spy thing, Clint had said dismissively when Tony ridiculed his paranoia.

So they'd come here, one of what Tony called his "idea labs." He had at times worked on his own projects that he wanted to keep away from cameras or microphones, and had employed scientists and engineers who made similar requests, so Stark Tower had a half-dozen surveillance-free rooms for those occasions.

He'd been irritated when Clint had then turned around and criticized the room as a security weakness. It was a SHIELD thing, Tony decided, to never trust anyone or anything.

Speaking of which. Tony entered the room and closed the door behind him, sealing the room.

"I was trying to figure out how you got in here without setting off any alarms," Tony drawled by way of greeting, "but then I got the message that there'd been a couple security cards stolen."

"Your staff shouldn't leave their pass-cards in their lockers at night," Clint smirked, tossing three key cards onto the desk nearest Stark. He was in a t-shirt and jeans, with no sign of his weapons or costume. "Thanks for playing along."

Tony folded his arms across his chest defensively. "You better have a good reason for this, Barton. Otherwise I'm locking down this whole building and kicking your ass."

Clint held his hands up near his shoulders, palms out, in a sign of surrender. "I'm unarmed, Stark. Like I said. I'm just here to talk."

"Why? Nothing you say could convince me that you're not a Skrull."

"But you're not."

Nothing could have thrown Tony off quite like that statement. "Huh?"

"I've been thinking about it," Clint continued, hands falling to his sides. "Obviously the Skrull are really good at imitating people. Extremely good. I'd met Viper before and I could've sworn that was really her on Hydra Island: she sounded right, looked right, acted right. But copying another person doesn't mean copying their brain and emotions, how they think and feel."

"How do you know?"

"I don't. It's a guess, I'll admit, but I'm pretty sure of it. How could you risk changing the way your brain works without changing yourself? If these guys are working undercover on some long-term infiltration plan, then they work, psychologically, just like a spy network. And every spy knows that you can look or sound like the enemy all you want - it's when you start to THINK like the enemy that you're a danger to your team."

Spy things again. "I don't see what this has to do with me."

Clint grinned. "I'm only going to say this once, Stark: you're a genius."

"Normally appealing to my ego is a safe bet, I'll admit."

"No, really. You're a genius. Certifiable. You don't just know things, you see things in a completely different way. I don't think any Skrull could copy you convincingly, because they wouldn't be able to think like you. That's why Fury approached you, out of the whole team, to show you the Skrull, and that's why I'm talking to you now."

Tony has to admit, that made a certain amount of sense. "It's not a completely bulletproof argument."

"No, but it's solid enough. Plus, even if a Skrull could pretend to be as smart as you, I doubt it would be able to pull that off while also being just as much of an asshole."

Tony gave Clint a narrow glare, but the blonde just smiled back. "So you came here just to tell me that you think I'm still me? I'm touched."

Clint shook his head. "I came here because you're still you. I came here to tell you that I think I've figured out who IS a Skrull, and I can't act on that information alone."

"You still haven't proven that you're not a Skrull."

"I know, and I can't. Not really. Just, bear with me for five minutes. Let me walk through this, from my point of view, where I know that I'm me, and at the end if you think I'm trying to trick you we both walk away, no harm done."

It was tempting to say no, but more tempting to say yes. All pride and rumor aside, Tony was smart enough to know when to take input from other sources. That input wasn't always valid in itself, but it could eventually lead to the truth.

Besides, he had nothing better to do.

"Okay, Hawkeye. Let's hear it."

He could see Clint visibly relax, and then start to pace, as the archer tended to do when he was talking. "The first question I had to ask myself was, why WOULDN'T the Skrulls want to replace me?"

"I'm not sure this tower is big enough for your ego, Barton."

"Ha ha. Seriously, Stark. The Skrull Viper had me, Widow, and Mockingbird alone and vulnerable. We should all be Skrulls. So why aren't I?"

"Like you said, I'm keeping in mind this is your point of view," Tony drawled, though, despite himself, he was interested to see where this was going.

"Think about it. I'm a wild card. Sometimes I work with the team, sometimes I don't. Sometimes I'm selfish, sometimes I'm selfless. I have the skills to drop off the radar and throw monkey wrenches into plans. To sum up: I'm more valuable to the Skrulls as I am. I could cause more difficulty and suspicion than even a Skrull pretending to be me."

Tony blinked in surprise. "I'll give you ten bucks to say that again into a tape recorder."

Clint rolled his eyes.

"But, okay, you make a fair point. IF you're not a Skrull."

"So, if they didn't want me because it's too much trouble to BE me, then they must have a much more complicated and intelligent plan than just taking us down one by one, right?"

Tony shrugged. "It's a fair guess."

"Look at how well being revealed worked out for them. We found out about their presence in exactly the way that divided us the most."

"You're saying they planned for Mockingbird to catch Viper?"

"Maybe not Mockingbird," Clint admitted, "but Viper, absolutely. Widow had enough time to see how good her act was but they weren't close enough for Tasha to have picked up on anything that might have given Viper away. And the fact that the only communication they could find was to the Avengers? You really think an alien race that can impersonate humans perfectly couldn't figure out how to hide that kind of trace?"

Tony had to admit, Clint was making more and more sense. He still kept reminding himself that Barton hadn't proved himself NOT a Skrull, but if he wasn't Tony realized that he hadn't given the archer enough credit for his unique brand of intelligence.

After all, Clint was the only normal human Tony knew of who, having been cornered in an alley, had simply vanished right out from under all the other Avenger's noses.

Clint kept going, unaware of Tony's changing mood. "If I can assume that I'm not a Skrull because impersonating me is just too much trouble and risk, I can say the same about the Hulk and Thor. Sure, maybe they have the technology to mimic the Hulk or make a copy of Thor's hammer, but why go through the trouble? Plus it would be more trouble and risk to restrain the real ones. We've only ever seen Thor restrained by his people's magic, and the Hulk never stays locked up for long."

"I had the same thoughts. But it is possible. We don't know how powerful the Skrulls are."

"But it would be trouble. A lot of trouble, and risk. Not fitting this grand master genius plan."

Tony nodded. "Then you could say the same about Nick Fury. No one ever knows what he's really up to, or what side he's playing."

"And Widow. The only people who trust her at all are Fury and me." Then Clint's expression changed, a shadow passing over his face. "But Morse "

Tony couldn't help but feel his own gut twist slightly at the thought of the young woman. "Loyal. Human. Unimportant but right at the center of things."

"She's a perfect target," Clint finished, remorse audible in his tone. "And she's been acting suspicious."

Tony frowned. As far as he recalled, Mockingbird had refused to see Clint after the Hydra Island incident and then vanished with Fury off all radars. "When?"

"Exactly. Look, I'm not gonna get into the details with you, but my what's going on between me and Widow and Mockingbird is complicated. We all know that. It's like some crazy game we're making up as we go. Bobbie not wanting to see me at all is weird, but I think, if a Skrull replaced any one of us, with our memories, it would be scared of that game."

Tony opened his mouth to protest, but Pepper sprang to his mind. Their seemingly unending dance around each other, their dozens of layers of teasing and sarcasm; even with all of his memories, or Pepper's, could anyone really hope to impersonate that perfectly? "It's risky. Very risky."

"And doesn't fit the master plan theory."

"Okay." Tony sat down heavily in a swivel chair and rolled himself over to a desk, where he grabbed a pencil and paper. He wrote down the names of everyone who had been part of the Avengers and the main players in Shield. He crossed out himself, Widow, Hawkeye, Thor, Hulk, and Fury, and circled Mockingbird. "That leaves Wasp, Ant-Man, Panther, Cap, Miss Marvel, Director Hill, and the whole rest of the world."

"You can cross out Miss Marvel."

"Too much trouble?"

"That, and she got her power from the Kree. If they've been fighting a war for years, logically the Kree would design their weapons to be anti-Skrull, and vice versa. I don't think they'd want to risk trying to take her down and keep her down."

Tony crossed out Miss Marvel. "You know this is all guesswork, in the end."

"Guesswork and gut instinct. Two of humanity's best assets."

"If you're right, I think we can also cross off Hill. If the Skrulls are deliberately leaving the suspicious targets alone, her insistence on bringing in the Avengers is too good an excuse. Too obvious." He crossed her out, but with dotted lines and a question mark.

"Then you can cross off Pim for the same reason. Deliberately leaving the team?"

"Yeah, and now he's given up his costume. The new guy might be a Skrull, but he's not a concern right now." Making another dotted-line X, Tony glanced over the remaining three names.

"Panther's tricky, but I'd say it's likely that he's himself. Partially cause he's smart, like you, partially because he left, and partially because a lot of his tech is secret stuff that only works for him, and no one knows if that's science, magic, or both."

Clint pulled up a chair and leaned back in it. "Plus, if Panther's been switched, there's not much we can do about it, what with him heading home, but if he were the only Skrull on the team he wouldn't leave the country without leaving someone to keep an eye out. So either Rodger or Janet has to be a Skrull, and I think I know how to test them both."

Tony looked up. "How?"

"Kill me."

He blinked. "Tempting as that sounds "

"You're the only one of us who's seen what a Skrull looks like. I'll bet with your technology we can make it look like I'm a dead Skrull. You can say that you decided Fury was right about me, and took matters into your own hands."

"And watch their reactions," Tony added, following the plan.

"On camera, preferably, so you can slow it down for micro-expressions." Clint paused, then looked Tony straight in the eye. "That is, unless you really think I am a Skrull."

Tony let that hang in the air for a moment as he observed the blond man. Without his uniform or weapons, Barton looked strangely normal, like any other lean blond man of his age.

It was ridiculous, really. Hawkeye? The guy who tore through Hydra and AIM just to get revenge on a woman wasn't this calm, collected, critical thinker. And yet he was. Clint's skill in reading his enemies for their patterns and weaknesses was part of what made him so deadly, what put a human with some trick arrows on a team with superheroes and geniuses. It was everything no one would ever expect from the man, and exactly what he did best.

No matter how many memories or mannerisms a Skrull copied, there was no way they could be a 100% perfect copy of the original. Tony had to believe that, and he knew why, despite all the arguments they'd made, Clint wanted to believe it, too: because if that was false, then humanity was screwed.

No one trying to impersonate Clint would do something this crazy, but it was exactly the kind of crazy that only Clint would do.

"No," he said finally. "I hope I don't regret it, but I think you're you."

Something flickered in Clint's eyes, and Tony realized that both of them had unconsciously relaxed, just a fraction. They weren't alone in this anymore.

"All right. Let's turn me green."