Disclaimer: I don't own Supernatural or Doctor Who or any of the related rights.

...

Sam stared in dismay at the door behind them, but then River had her hand wrapped around his arm and started dragging him away. "Hide!" she hissed in his ear, and he heard the approaching footsteps and knew she was right.

Didn't make it any less frustrating, though.

They ducked into a side room and slammed the door shut not a moment too soon. They could see through a window panel in the door as the Cybermen passed them, and they ducked back down, waiting for them to pass. River gripped her sole remaining blaster, and Sam wished he hadn't let Amy run off with his gun—for all the good he knew it would do. He had a knife strapped in his boot, but that probably wouldn't be much help, either.

"How did we get through and the others didn't?" Sam asked in a whisper.

"This ship's falling apart at the seams. Ion storm, I'd bet, though obviously not as strong as the ones that destroyed the Cybermen when the Doctor first met Deeva," she observed.

"You know everything, don't you?"

"Everything I can get my hands on, yes," she said, grinning brilliantly. "I went to school to study the Doctor."

"I thought you studied archeology."

"Exactly."

Sam frowned, but then, just to break the tension, he laughed and said, "And think—I went to school to study law."

"You'd have made a fine lawyer. You're stubborn enough to win your cases," River said.

Sam wasn't sure if that made him feel any better.

They heard Cyber-footsteps approaching and ducked down again, practically holding their breaths. Through the door, they could hear muffled shouts, but the metal comprising the ship was thick, so they couldn't hear all the words.

"Sounds like Rory," River said, her eyes wide and worried.

"You know him well?" Sam asked.

"He's my—" She stopped and checked herself. "He's one of my best friends."

Sam raised an eyebrow.

She waved him off. "Come on," she said. "Let's see if we can't follow them."

Sam grinned and stood up. He reached into his boot for the knife, if only because he felt a little bit safer when he had something with him, no matter how feeble. River raised an eyebrow at him but didn't say anything.

They both signaled a countdown to each other—three, two, one—and opened the door as quickly but as quietly as possible.

They saw a flicker of something rounding a corner, but easier to follow were the shouts of "You take your hands off her—she's my patient!" and "Stop pushing!"

"Rory," River breathed out in relief. Then, she laughed, "He's leaving us a trail to follow. He's never that loud."

"I didn't think he was," Sam said. He'd trounced the man in board and card games and hardly got more than an exasperated sigh; he'd seen Rory fight Cybermen with something like the memory of military training in his eyes. He didn't seem like the drawing-attention-to-himself type.

They were able to keep a safe distance behind the group because Rory was so loud, and that even gave River the opportunity to whisper, "I think that was a people trap."

"As opposed to a mouse trap?" Sam asked.

She rolled her eyes. "I mean it was meant to separate us. Teammates on opposite sides of a wall tend to try to find a way to get un-separated. That's why the Cybermen came from our end; they probably expected to find us there, too."

"So they know we're still around?"

"I'm not sure."

"You're a real comfort," Sam frowned and gripped the knife tighter. He'd promised Dean a nice night out, just to get out the gloom. And it wasn't even a hunt, where they could both kill things nice and simple and get out some frustration. It was space, and they had no idea how to fight these things.

"Your knife won't help," River said quietly.

"It helps me," Sam said.

"Uh-huh," River said.

Sam went to round a corner, but at the last second, River grabbed him by the collar and dragged him backward. He opened his mouth to protest, but she just put a finger to her lips.

Sam opened his mouth to argue, but then he realized what had made River stop in the first place: It had gone quiet.

Too quiet.

They hardly even had to look at each other before they both went sprinting in the opposite direction. They found the nearest open door and flung themselves inside, breathing heavy. They heard gunfire (or was it laser-fire?) in the hallway, and then they heard Cybermen clomping around the hallways.

"There goes the element of surprise," River laughed. Her eyes were sparkling with the excitement.

"No wonder he likes you," Sam panted. "You like this!"

"Tell me you don't—I dare you," River countered.

"I really don't," Sam said. "Not the monsters part, anyway."

River just laughed again. "You're the stick-in-the-mud want-to-be-normal brother, aren't you?"

Sam rolled his eyes at her, but then there was a Cyberman by their door, and they both fell silent.

The Cyberman tried the door, and Sam looked at River with wide eyes and a question in his gaze: did they lock the door?

River indicated the console above her in answer. Yes, she had.

But that apparently wasn't enough. The Cyberman must have realized they were in there—scanning for life signs, or maybe sensors in the room, Sam didn't know—and Sam and River heard the beep beep beep of buttons on the outside console.

"So," Sam said, trying to keep his head as River tried to weld the lock in place with her blaster (it wasn't working as well or as fast enough as either of them would have hoped), "anything kill these guys?"

"This version?" River sighed. "They look like they're based on the older models, so gold might help. Shooting them head on enough times with a blaster can also do it. If you get off enough shots and your aim is as excellent as mine is."

He gripped the knife. "Don't have much gold," he muttered. "I'm more a silver person."

"Yeah, Dean said that works on shifters and stuff," River said.

"Fast learner."

She shot him a quick grin before she grabbed him by his coat and dragged him behind her. "Soon as that door's open, I'm going to see if I can't blast him enough times."

Sam nodded, but then a thought occurred to him. He remembered something Dean had said about the Zygons, and he flipped the knife into his fist, rushed over to the control panel, and jammed the knife in.

It had the opposite intended effect. Sparks flew everywhere, and the door sprang open. The Cyberman marched inside with robotic shouts of, "Halt. You will surrender," and other things like that.

River let out an exasperated sigh, but that was the only indication she gave that acknowledged the fact that Sam had definitely just messed up their chances.

Some of River's shots pushed the Cyberman back with the force of their impact, but it groaned mechanically and pressed forward, arms outstretched.

River shot it a few more times until, finally, it collapsed.

Sam grinned at River. "Nice shooting, Tex," he said.

She flipped the blaster over in her hand. "Ain't nothin' to it, partner," she said in a bad impression of a cowboy accent.

He laughed, then grabbed her hand to rush her out the door while they still had a chance before they got blocked off by another Cyberman standing in their doorway—right into the arms of two waiting Cybermen!

Sam heard River's blaster go off beside him, but he couldn't turn his head to see because there was a strong, silvery arm pressed against his upper chest and throat, pinning him to the wall.

Well. This was not going well.