A/N: Thanks for reading and reviewing everyone! I'm not too sure about Sarah's POV in this chapter, I find her hard to write, but I hope it's OK and you enjoy it. Oh, and huge cliffie at the end, because I am evil.

A sudden silence descended over the room, followed by the thudding of twelve men collapsing unconscious to the floor.

"What just happened?" Sarah asked, as the man she was fighting fell away from her, the last of the black smoke leaving his mouth and disappearing through the floor. For a second, as she had glanced across the room just before the smoke, the shadows of giant wings had seemed to flash across the wall behind Castiel.

The Winchesters and their friend seemed just as dumbfounded as she was. Sarah found that less than encouraging, because something monumentally strange was going on, and she'd kind of hoped they knew what they were doing.

Sam broke the silence, saying: "What happened? I thought you weren't an angel anymore, Cas."

"I forgot," Castiel replied solemnly, and Dean started to laugh.

"This is awesome," he said, but then his smile faltered almost imperceptibly as he realised something. Sarah probably wouldn't have noticed if she hadn't been trained in lie detection.

Then Dean said, "Does this mean you're leaving?"

Sarah could tell it was meant to be casual and nonchalant, but it came out small and slightly broken, and it made her heart ache a little bit.

"Could we continue this beautiful moment later on?" Casey growled, "We've still got an arms dealer to catch."

Sarah never failed to be amazed by his single minded ability to focus on the job, particularly when Chuck was not in the room. Chuck seemed to impair Casey's ability to concentrate.

Sam seemed to suddenly remember something, and exclaimed something that sounded a lot like "Oh Crap! The ghost!"

Sarah looked at him, tearing her eyes away from watching Cas try to have a silent conversation with Dean, and Dean steadfastly refusing to meet his eyes.

"What is going on?" She asked Sam, but he didn't reply, because he was mumbling something about ghosts and witches and demons all being in the same place, and it not being a coincidence. The really scary part was that Sarah was starting to think that he wasn't crazy. If Cas was really an angel, then apparently the people they had been fighting were really demons. She was very glad she hadn't known that at the time.

"Dean," Sam said gently. It seemed to rile his brother, who glared at him, but began to take action again.

"You two stay here," he told Sarah and Casey. "They'll be waking up soon, and they'll need help. Some of them are injured. Don't worry, the demons are gone. If another one comes, splash it with holy water and say this –" Sam handed Sarah a flask and scribbled something in Latin on a page he tore out of a notebook. Sarah couldn't help thinking that he must have deceptively large pockets.

Sam, Dean and the angel of the Lord left the room. As they closed the door behind them, Sarah heard Dean say: "A demon-possessed arms-dealing witch raised a murderous spirit from the dead. This should be fun."

Casey left, too, carrying Morgan back to Castle for some first aid, and Sarah was alone in the room with twelve recently-possessed unconscious men, many of whom were starting to stir.

She was checking the pulse of a tall man wearing a cheap and new-looking imitation of Sam's outfit, when the door opened. She spun around, gun raised, before remembering it wouldn't work on a demon.

Chuck stood in the doorway, in full bulletproof vest and raiding gear. He grinned when he saw her, and she lowered her gun. She smiled back, relieved he was ok. But as he rushed over to her, something didn't seem quite right.

She realised why when he lifted his gun to her head.

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Chuck couldn't control his body. The black smoke had slammed into him somehow, and now it was inside him, making him do things he didn't want to. It tossed his phone to the ground and stepped on it, crunching it to tiny pieces with his combat boot before Sarah could answer.

"Sarah," it said, inside his head, "yes, that's a good place to start. She's a pretty one. I bet she'll try to fight, too. It's always more fun when they fight."

No, thought Chuck, please no, not Sarah. But he felt its amusement, and heard it laugh with his voice as it checked the clip of his gun and slotted it back together decisively. Chuck saw with horror that there were real bullets in there, and cursed himself for not replacing the gun with a tranq before he left.

It didn't bother to open the door of the BuyMore, just smashed it with a flick of his hand, sending shards of glass cascading across the parking lot. Chuck felt a slight jolt of satisfaction when he realised the silent alarm must have been triggered.

"Be careful what you wish for, Chuckles," said the voice inside his head, "Police, CIA, NSA, it's all just more people for us to kill. Humans are no match for us."

Then how did Dean and Sam ruin everything? Chuck thought vindictively, trying not to think about the huge numbers of imminent deaths and failing miserably.

The demon did not reply for a moment, marching Chuck's body away from the BuyMore, toward Sarah's murder. Chuck twisted and struggled, and concentrated his whole soul on stopping walking. Turning around. He would not kill Sarah. He would not kill anyone. Chuck's footsteps faltered, and for a second he thought he might be winning, but then the blackness inside him took over once more and his feet carried him smoothly onwards.

"Trying to escape, Chuck? Are you really that naive? Do you really think I can't see inside you? I know killing doesn't bother you as much as you pretend it does. You killed Shaw, and now you're glad he's dead. You hated him because he was with Sarah, didn't you?"

No, no, that's not how it was, Chuck thought desperately. He hated killing. It made him sick, and he had nightmares about Shaw every night, seeing his bullet ripping into him, Shaw's body tumbling from the bridge.

"Maybe it wasn't how it looked. Maybe Shaw really was a double agent, and he was on your side. Maybe no-one had to die that night."

Chuck just kept thinking no, no. He passed Casey in the dark, and felt a rush of panic as he saw Morgan's unconscious body draped over his shoulder. Casey grunted at him, and Chuck felt his head nod in reply, and heard the darkness say with his voice: "Where's Sarah? Is she OK?"

Casey grunted again, nodding that she was unhurt, and pointed, then set off back to Castle, saying something about fixing Morgan up and coming back.

Chuck's body marched purposefully around the back of the building, loaded gun in hand, and pulled the door off its hinges.

The next door, it didn't pull off the hinges, but opened gently, quietly. Sarah was inside, checking the pulse of an unconscious man. The demon seemed shocked as it surveyed the twelve unconscious men, and its smug taunting stopped. Something had gone wrong with the plan. Chuck smiled with relief at seeing Sarah in one piece, and satisfaction that the demon's plan was going awry, and he felt his face move with it, in his control for that instant that the demon was distracted. Sarah lowered the gun she had raised when he entered.

But the demon reasserted its control too soon, and Chuck felt his face morph into an expression of false concern. Not that Chuck wasn't concerned, but the demon certainly wasn't worried about her. His body rushed over to her, and his voice asked worried questions about what had happened and if she was OK. Sarah seemed disconcerted, though, and did not answer them.

And then Chuck's hands raised his gun to her head.

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