The shrieking of the alarms finally - blessedly - stilled, aside from one warbling trill somewhere downstairs. Kevin sank against a wall, heart still pounding, and laced his fingers together to try and stop their trembling. It took several moments before the adrenaline started to go sour and he was able to take a deep shaky breath and turn toward the stairs.

The pounding on the door nearly made him stumble, his lungs freezing as his mind flicked through the possibilities and options he had. There was someone at the door. The alarms - whatever they had been for - had just sounded. They could have gone off for whoever or whatever was at the door. Kevin should stay upstairs, be very quiet, and pretend to not exist. He was good at that.

The pounding came again - more staggered, weaker. It didn't have the same threatening thunder from before. Kevin leaned over the railing to stare at the door. It could be the Winchesters. Kevin had the key, after all - and it didn't seem likely that they had made copies, considering the box it had been stored in. They hadn't said how long they would be gone. Now that he thought about it, they hadn't said they would be back at all, but his mind shied away from that line of reasoning.

Again. Just once, a single impact against the door, with an unmistakable desperate sound to it. Kevin hesitantly descended several stairs without realizing it before stopping himself.

The pounding did not come again.

If it had not been so silent - even the tinny alarm upstairs had quieted by now - Kevin might not have heard it, given how thick the door was and the insulation of the hill into which the bunker was built.

"Dean..."

For the third time in a very short span, Kevin's stomach dropped in a deadly cold lurch and he flung himself down the staircase, jumping down the last several steps as he launched himself at the door. He did not exactly fling it open, heavy as it was, but he did wrench his shoulder painfully as he tried.

The scene before him was not what he'd expected. For that voice to sound that weak, he'd expected blood. Bruises. Contusions. He'd expected the overcoat to be torn, the white shirt nearly black with an unmistakable dark stain.

Instead, Castiel looked nearly pristine, slumped against the doorframe, holding his side. Kevin tore his eyes away from the survey of the nonexistent injuries to meet Castiel's eyes, and his breath caught.

"You're not Dean." If Castiel's voice had not been trembling, it could almost have been accusatory. Light glistened off his tearstained cheeks. "This is the Bunker. Where is Dean?"

Kevin blinked. "I - I don't know - Cas, are you hurt?"

Castiel seemed unable to focus his eyes; they stared straight ahead, as though piercing some veil that Kevin couldn't see. "I need Dean."

"I don't know where he is. Are you hurt?" Kevin repeated, peering to try and see why the angel was clasping his hand so tightly against his side. "What happened?"

"I...?"

Castiel's eyelids fluttered and his chin nodded forward. Belatedly, Kevin reached out a steadying hand, which by necessity turned into a grip on the angel's arm as Castiel's legs folded and Kevin eased him to the ground as gently as he could.

"Cas? Cas!" Kevin fumbled for a pulse, but felt nothing - would an angel even have a pulse? They breathed, and Castiel was still doing that, but his eyes were dilated and staring into middle space and try as he might, Kevin could not find any spot on Castiel's neck or wrist where there was so much as a flutter.

He was not altogether sure how he had made it upstairs to his backpack, nor how he had dialed his phone with such shaky fingers.

"911, please state your emergency."