Title: It's Never the Little Green Men

Author: Jedi Buttercup

Disclaimer: The words are mine; the worlds are not

Summary: John could hear the pair working the Wraith crime scene before they saw them: a rather excitable male voice doing most of the talking, and a firmer, slightly amused woman, offering the occasional counterpoint. 1800w.

Rating: K+ / PG

Spoilers: Post-series for Stargate Atlantis; vague timeline for Castle

Notes: For debirlfan, who asked for "Castle + Stargate Atlantis. Either Rick has the Ancient gene, or there's a wraith killer loose in NY. (Or both.)" Title's from a quote in Castle 3.9 - "Kate: We will continue our investigation and solve this case and it will have nothing to do with little green men. Castle: They're grey, actually." Though this fic is roughly set before that; Atlantis landed on Earth in January 2009, and Castle started airing in March of that year. Originally posted elsewhere 11/30/15.

They could hear the pair working the crime scene before they saw them: a rather excitable male voice doing most of the talking, and a firmer, slightly amused woman, offering the occasional counterpoint. Familiarity nagged at John for a moment, then faded into nostalgia. The accents were all wrong, but he was reminded of the early days in Atlantis: Elizabeth and Rodney. He shared a knowing glance with Ronon, then held up a hand to slow up a little for the final approach to the apartment in question. He thought it might be a good idea to find out what the NYPD were making of the murder before they stuck their oar in.

This hadn't been the first death in the country in the last few weeks under circumstances suspicious enough to raise flags at Homeworld and warrant an Atlantis-based team; it was, however, the first time the body had been left where so many people could trip over it. None of the eggheads were sure whether that meant the Wraith's behavior was devolving, or if all of the previous drop sites had just coincidentally been rural and isolated.

The woman's voice carried out through the taped-off doorway, rich with wry indulgence. "Mummies. You're seriously looking at this guy and thinking 'mummies'. What, are you back to throwing ideas at the wall to see which one will stick?"

There were other police officers present, as well; one had stationed himself outside the apartment door, a detective by the badge on his belt and the cut of his jacket. John flashed his military ID at the man as he approached.

"Colonel Sheppard; and this is Specialist Ronon Dex," he introduced them. "It looks like you guys caught one of ours."

"Not mummies; the guys who made the mummies," the man's voice replied, indignantly. "Though the more I think about it, the more I lean toward aliens instead. I mean, the landlord said he saw Mr. Jones out jogging just yesterday with his dog; no way he turned into cordwood in less than twenty-four hours in this climate. You would not believe how gross the mummification process is; I researched it once for a Derek Storm idea I didn't end up using."

Derek Storm? As in the book character? Even having spent most of the last decade out of the country, John recognized the name; the advertising had been that pervasive. Surely the cops weren't dragging along a New York Times best-selling author? Well, whoever he was, he gave a pretty evocative vocal shudder.

The detective grimaced, but took the ID and scanned it over with a nod. "The victim? Or the killer? We haven't been here long; you guys responded awful fast," he said, suspiciously.

"Could be both; that's what we're here to find out," Ronon shrugged.

"White hair, wrinkled skin, and lack of ID do not proof of an alien abduction make," the woman continued from inside the apartment, more reasonably than her partner. "The simpler answer is that this isn't Mr. Jones. According the landlord, he doesn't have a roommate or girlfriend; maybe a homeless guy broke into his apartment awhile back. Mr. Jones killed him in self-defense, and was afraid to report it to the police."

"So he just left the body there?" the man scoffed. "A body that just so happens to have a matching tattoo on its wrist and a weird, fresh-looking wound on its chest? And nobody in this place reported the smell?"

"I didn't say it was a perfect explanation. But it's better than aliens," the woman fired back. Her tone conveyed an eyeroll even more convincingly than her partner's had his discomfort. "And I'm sure we'll find an even better one once you stop looking for evidence of little green men and focus on slightly more realistic possibilities."

Sheppard's eyebrows had climbed as the overheard conversation continued. "Are they always like this?" he asked the detective, sotto voce.

The detective smirked and chose not to answer, turning to knock on the door jamb instead. "Detective Beckett? There's an Air Force colonel out here, says the body may be one of theirs."

"Seriously?" Beckett's voice- the woman's voice; which was a relief to John- called back in exasperation. "We just caught this case."

"See?" her companion exclaimed, in faux-whispering tones. "The military's trying to cover it up! This time, it's definitely aliens."

"No, it's not aliens. They were waiting for this; that means it's a serial killer. Doesn't it, Colonel...?"

Beckett's voice trailed off as she reached the doorway, glancing between John and Ronon, then settling on John.

"Sheppard," John replied, nodding to her in acknowledgement. Detective Beckett was a tall, stylishly dressed brunette who, wow, did look a lot like Elizabeth, if maybe a little taller. The man behind her was John's height but more solidly built, dressed like someone in John's dad's tax bracket with kind of squarish, Hollywood good looks. Definitely the writer John had been thinking of: Richard Castle. Which, right; hadn't he heard the guy had been starting a new book series about a female detective? Talk about writing what you know.

Though John supposed he'd be one to talk about living a life that sounded like fiction, considering he was about to introduce an alien to a woman who'd just derided their existence. "And this is Specialist Dex. Officially speaking, I can neither confirm nor deny, Detective...?"

"Beckett," she said briskly as she held out her hand to shake. "This is Richard Castle; he's a consultant, and Detective Esposito. And unofficially speaking...?" She arched her brows.

"I still can neither confirm nor deny; though that's partially because you're both partially right," John gave Beckett and Castle both a sharp-edged smile.

"Partially right?" Castle repeated. "Which part?"

John shook his head. "That's all I can say; we'll be taking over the crime scene."

"Then I'm sure you have the appropriate paperwork for that?" Beckett pressed.

"Here." Ronon pulled an envelope out of his jacket and handed it over; the one General O'Neill had given them before they beamed out of his office. It only had the DHS logo on it- they couldn't exactly use 'Homeworld' Security out in public, not until the brass figured out how to bring the Stargate program out of the closet without causing a panic- but it was enough to get the job done.

Beckett's mouth flattened out into a line as she took it from him. "This isn't exactly regular procedure," she hedged.

"Take it up with your superiors," Ronon gave an eloquent shrug. "We're all just doing our jobs, here."

"Anyone else in the apartment?" John prompted her.

"Just the medical examiner," Beckett sighed. "Espo, if you'd go check on Lanie?"

"Sure thing." The detective that had been guarding the door nodded, then went inside.

"Look, we've worked in cooperation with other agencies before, even under extremely confidential circumstances," Beckett continued. "Whatever it is that brought you here, surely more pairs of eyes can only help."

"Unless it's classified because it's alien," Castle murmured to Beckett, in low, excited tones.

She threw him an irritated look over her shoulder. "Castle, not now; and you know it's never aliens."

"That doesn't mean it never will be. Absence of evidence is not evidence of absence, right?"

"Almost makes me wish McKay weren't tied up doing repairs on the city," Ronon muttered as the pair continued to argue.

John grinned at him. "Yeah, I know what you mean."

Surreptitiously, he pulled the Life Signs Detector he'd brought from Atlantis out of his pocket, seizing the moment of distraction. The thing looked enough like some kind of ruggedized tablet device that it wasn't very risky to use in public. Even if he lost it, the chances of someone else being able to get the screen to light up even dimly were one in a million, give or take a few hundred thousand. It had a range of a hundred meters or so, more than enough distance to check Beckett's claim. They were planning on beaming the body- and all the other contents of the apartment- straight up to the battleship in orbit the moment they were inside; he didn't want to risk accidentally bringing an observer along for the ride.

Unless, of course, that observer was the rogue Wraith itself, lying in wait. They still didn't know how it chose its destinations, or if anything tied the victims together beyond their being considered 'food'; there was no precedent for its behavior, and thus no way of predicting its next move. The quicker they found it, the better.

The scanner showed just the two inside, though; John was just about to pocket it again when a shrill, piercing scream from the floor below them startled him. He fumbled the LSD as everyone's heads whipped around, looking for the source, and winced as it clattered the floor, screen going dark.

"Fine," Beckett hurriedly said. "You can have the crime scene. We'll go check out that scream, and if it happens to be another victim..."

"Call DHS, and ask for General O'Neill," John said absently, crouching to grab the LSD.

Castle had moved at the same time he did, though; the writer's hand touched the case about two seconds before John's fingers would have. And... lit it up.

"Here, sorry... oh, hey, is that some kind of game?" Castle frowned, pausing as he made to hand it over.

"Again, not the time, Castle. Come on," Beckett said, hand on her holster as she made off toward the stairs.

John cleared his throat; wow, this was going to throw a wrench in the works. Unless...

He had a horrifying thought. When they did finally reveal the Stargate Program, someone was going to have to write about it, right? Someone outside their own scientific and diplomatic circles; someone with experience writing a compelling narrative who could get the average, everyday citizen to buy in and support their funding. Someone who had reason to be as enthusiastic as the 'natives'.

"Like I said," he told Castle, giving him a significant look. "If you have any more questions, call DHS. Ask for General O'Neill."

Though hopefully, John would get a chance to brief the general himself first. They'd never be able to get away with the usual contract, but a strong natural gene was still rare enough that the SGC would want to get their hooks into Castle somehow.

Castle seemed to get the seriousness of John's statement; all the manic excitement faded out of his expression, and he handed over the LSD with no further commentary. "Good luck with the investigation," he said by way of acknowledgement, then shouted something to Esposito and took off after Beckett toward the stairs.

John sighed, already tired of the day, then followed Ronon into the apartment.