Disclaimer: I don't own 'em

Spoilers: None that I'm aware of.

Author's Notes: Unfortunately Season 3 has not yet started here in Australia so I haven't seen it. On the bright side, I've been filling in my time by writing this fic instead. Thanks to Tanya Reed for the great beta work.

Rating: T (purely due to the subject matter)

"It's the freakiest thing I've seen in a while," Detective Javier Esposito commented as he surveyed the crime scene in front of him.

"Yet, also the coolest," Rick Castle stated with a grin, looking around the garishly decorated hotel room. 'Cheap and nasty' sprang to his mind as a description, but he supposed it looked clean enough... just.

"I don't think their parents would be pleased to hear either of those assessments," Detective Kate Beckett pointed out. Her glare was met by chastened looks from both men. Turning to one of the other people in the room, she asked, "Lanie, what can you tell us?"

"Not much," the ME replied. "R2-D2 over there was bashed over the head. That," she paused, wondering what term to use.

"Cyberman," Castle supplied helpfully.

"Right. The Cyberman was shot, guess the armor wasn't bullet proof. C3-PO was also shot." She turned to the next fatality. "The -"

"Dalek," Castle cut in.

"I knew that one!" Lanie Parish glared. "The Dalek I'll need to get back to the morgue to assess, and determine whether the bullet or the stab wound to the jugular was the cause of death. Guess he shouldn't have gone for the flexible neck costume option."

"And that one?" Beckett asked, looking at the last remaining body.

"Princess Leia over there was stabbed, as you can see."

"The lightsaber? Really?" Castle queried incredulously. "Coolest case ever!"

"Castle!" Beckett glared. "And put the phone away! How many times I have told you, no taking photos at crime scenes!"

Castle nodded his head, but turned away to take a few more sneaky photos while Beckett spoke to Ryan.

"Any IDs?"

"The girl is Annie Dunkley, according to her driver's license," Ryan told her.

"No wonder she prefers to be Leia," Castle commented, earning himself yet another glare from Beckett.

"Anything on the others?"

"Not so far. The room's in her name. She checked in alone."

"The hotel staff couldn't tell you anything?"

"Haven't shown them the photos yet," Ryan said, "but the manager is waiting for me downstairs."

"So, was this some kind of costume party, or what?" Beckett wondered.

"According to the front desk, there's some kind of sci-fi convention going on."

"No there's not," Castle argued immediately, drawing surprised glances from everyone else in the room. "There's not," he insisted, "I'd know about it."

Beckett grinned. "Should have known you were that much of a sci-fi geek, Castle."

"Proud of it," he stated. "There's not a convention, though, not right now. Or at least, not a decent one."

"They're just kids," Esposito pointed out. "Maybe it's a college thing? Her license says she's from Pennsylvania, but she could be a student here in New York, though there's no student ID with her stuff."

"In a hotel room? If it's just some college thing, you'd think it would be held there, no need for them to stay in a hotel." She turned to Ryan. "You and Esposito work the hotel, talk to the staff and the neighboring rooms, see what you can find out. Any cameras?"

"Lobby only," Ryan replied. "Not exactly a high class hotel. I doubt they want to catch much of what goes on here on camera."

"Unless it's for blackmail purposes," Castle commented. The others nodded in agreement.

Esposito and Ryan left the room to carry out their investigation and Beckett turned back to Lanie. "Time of death?"

"Tough to say for sure until I do the autopsies, but I'd say sometime between one and three am. Esposito said that housekeeping found the bodies about an hour ago." Beckett nodded, having already been informed of that en route to the scene.

Beckett started wandering the room, taking in the scene and trying to formulate some idea of what might have happened. Castle, on the other hand, had stopped sneaking photos and was now jotting things down in his notepad.

"You got a theory?" Beckett asked, indicating the pad.

"No," he shook his head. "Just got to capture every detail of this for the next poker game discussion."

Beckett rolled her eyes and let out an exasperated sigh. "The Cyberman, what's that from?" Castle looked at her blankly and she rephrased her question. "I know R2-D2, C3-PO and Leia are from Star Wars and I know the Dalek is from some British show, but I don't know what the Cyberman is from."

"You really need to keep up with pop culture, Beckett," Castle told her, shaking his head in pity. "That British show is Doctor Who, one of the best science-fiction shows ever made. The Daleks are one of the enemies against the Doctor, the Cybermen are another."

"So, the Cybermen and the Daleks work together against the Doctor?" she asked, looking for any piece of information that might be useful to the case.

"No, no, no," Castle replied, making a mental note to introduce Beckett to the wonders of 'Doctor Who'. "The Daleks and the Cybermen are rivals. Both are enemies of the Doctor, but they're also enemies of each other."

"So, the fact they're in the same room here..."

"Just fans being fans. Though if Lanie tells us that the Dalek killed the Cyberman, or vice-versa, then this case will get even cooler!"

"And your little fanboy heart will beat right out of your chest," she chuckled, then laughed more heartily when he didn't make any denial.

TBC...