"Peter, come on, you know that dead bodies aren't really my thing..." Neal was complaining as the Taurus came to a stop outside the four-story brownstone, Peter had pulled it in nose-first between a pair of blue-and-whites, slapped the FBI-issue ID card onto the dash and got out, ignoring Neal's protests as he badged his way through the crowd towards the yellow crime-scene tape blocking the front door.
"Neal, the NYPD called, the murder's been linked to a series of high-profile art thefts, and I owe the investigating detective a favour."
"How does the great Peter Burke become indebted to a lowly NYPD homicide detective?" Neal asked, sticking close to Peter as they climbed the stairs, following the M.E. staff towards the third floor.
"You call Detective Beckett 'lowly' to her face and somehow survive, and I might tell you what she did for me to mean that I owe her a few favours."
"A few favours?" Neal asked as Peter pushed open the door, a half-smile playing about the agent's features as Neal paused on the threshold, that 'will I run or will I stay' look that Peter was so familiar with in his eyes.
"Detective Beckett, you rang?" Neal stepped into the room just as a dark-haired woman in her mid-thirties stood up from beside a body, smiling in greeting at Peter and snapping a pair of purple crime-scene gloves off in order to shake his hand.
"Hey, Peter, great to see you. About the case..." Neal allowed the detective's voice to become as background noise while he surveyed the room, trying to look everywhere but the man on the carpet with the hole in his forehead, a pool of blood on the carpet beneath him. It didn't take him long to identify the only other person in the room who wasn't a cop.

Not with that haircut.

The guy in the green shirt, about Peter's age, wearing denim jeans and a dark blazer, was hovering over the M.E.'s shoulder, grinning like a kid in a candy shop as he pointed out something on the body, making the M.E. shake her head and swat his hand away. He wasn't a cop, and dressed like that, he wasn't part of the M.E.'s team, who the heck was he?

Neal picked his way across the room, careful not to step on or touch anything, keeping one eye on the guy in green as he did.

He noticed several things about the man as he got closer, for a start, he seemed comfortable around the body, an attitude reflected only in Detective Beckett and the M.E., everyone else looked at least marginally uncomfortable about the cadaver on the floor. He was familiar with procedures as well, a pair of purple gloves covering his hands as he examined the body, but still not touching anything. He managed to attract the detective's attention once she and Peter were done with their greeting, pointing to some marks on the corpse's neck and mentioning something about 'post-mortem bruising'. The detective looked at the M.E., who nodded in agreement, before thanking him and asking him to leave her crime scene.

The guy's grin was suddenly smug, and Neal's eyes narrowed in recognition- where had he seen that smile before?

He hadn't quite remembered when the man suddenly stood up, taking a step backwards and to his left, colliding heavily with Neal and sending the pair of them crashing to the carpet just inches from the edge of the pool of blood on the carpet.

"Castle!"
"Caffrey!"
"What?" They asked in unison, each addressing their respective handlers, then looking at each other, Castle still half on top of Neal, his elbow digging into Neal's ribs.
"Castle? As in Richard Castle, the author?"
"That's me, and you're Neal Caffrey, aren't you? Weren't you a wanted fugitive a few weeks ago?"
"Oh, you saw that? I hate that picture." Neal muttered, thinking that it would be a great idea if this guy would get off him sometime soon.

As if he realised just how awkward the situation was becoming, Rick shifted, trying to get up and apparently failing, before Detective Beckett sighed and caught him by the wrist, hauling him to his feet with a stern look.

"You better not have contaminated my crime scene, Castle." The M.E. commented dryly, not looking up from the checklist on her clipboard. "Same goes for you, Mr Caffrey."
"Ye of little faith." Neal muttered, glancing half-hopefully at Peter before realising that he was going to have to stand up under his own power and struggling to his feet.
"Hey, don't glare at me, he knocked me over." Neal pointed at Castle, who was brushing himself off at a safe distance from the body, but paused when he realised that the conman was talking about him.
"Hey, you snuck up on me!"
"I was trying to get a closer look at a crime scene, and you didn't look around before you bashed into me." Neal countered, snatching his hat up off the floor and taking a step backwards so that Peter was between himself and Mr Castle.

Rick conceded with a grunt, nodding at Peter as if to admit defeat. Neal returned the hat to his head with a flourish, something akin to a smirk directed at Castle, making the writer do a double-take.

"Hey!" Castle exclaimed, and Peter spun around in time to see Neal straightening his hat with a rather over-zealous look of concentration. Peter caught him by the elbow and dragged him out of the room, past a pair of uniforms and into a neighbouring room.
"Hey, you pull your head in, we're co-operating with the NYPD on this one, and Castle's riding along with Beckett thanks to a deal he struck with the Mayor, so he's in a slightly less precarious situation than you are. Play nice."
"He knocked me over!"
"He didn't do it on purpose, stop being so damn precious and get back in there- Beckett thinks that the painting over the fireplace is a forgery that's been put in place to cover the theft of the original, which happened right before the murder."

Neal stuck his bottom lip out for a moment, pouting a little, before Peter gave him the 'menacing' look that Neal himself had helped him perfect, and he admitted defeat.

"Fine, but for the record I do my best work alone."
"Well you're going to have to be a second-best criminal for this one, because Castle's riding along with Kate, so he's coming with us."

Neal looked as if he'd been punched in the stomach, and it took Peter a moment to realise why.

"Ka-kate?" Neal asked, actually reaching out to grab Peter's shoulder to steady himself.
"Oh, dammit, I didn't tell you, Detective Beckett's first name is Kate."
"Oh, okay. Thanks for the heads up." Neal took a moment to gather himself, and in those few seconds Peter saw the vulnerable little boy that Neal became when he was under threat, the little boy in him that made Peter so determined to keep him out of prison, and on the straight and narrow.
"You think you'll be okay?" Peter asked, seeing that haunted look in Neal's eyes that was uncomfortably familiar.
"Yeah, I'll be fine. I'll be back in there soon, just give me a second."
"Okay."

A/N

Bitten by the plot bunny. I got 1200 words out and then went back to my NaNoWriMo... I wish that story was flowing as easily as this did! Any suggestions/ideas for direction are more than welcomed.

The rest of the respective teams will be seen in the next chapter, which is already half-written, but I've gotten stuck with Neal sitting in Castle's chair near Kate's desk and Esposito trying to chat Diana up...