I've had this idea in my head since last year. This is set during Bloodlust when Sam was kidnapped by the Vampires.
Prologue
Sam stared at the vampire looming over him. The gag prevented him from being able to shout out for help or cry out in pain as the sharp teeth rammed into is all too fragile skin. As darkness swept over him he felt blood trickiling down his neck.
Dean sighed and glanced at his watch uneasily.
"Where's Sam?" He frowned and Gordon looked up.
"He probably went for a walk, he seems like take a walk kind of guy," he told Dean. Dean sighed again, frusteration built in it.
"Yeah, but it's getting late. Not like him to be gone for so long."
"So if you're so worried, call him." The suggestion felt simple.
Dean nodded and fished out the phone. It went straight to voicemail, which meant Sam's phone was turned off. Sam never turned his phone off.
Worry grew. Something wasn't right, something was wrong. He couldn't help but sense it.
"What's wrong?" Concern flickered in Gordon's voice.
"It went straight to voicemail." Dean's voice was tight. "That's not like Sam, to turn it off."
"You think he's in trouble?" Gordon looked at him and Dean bit his lip. Maybe he was just overreacting. Being extra paraniod because of the recent loss in their family.
No, something wasn't right here. Sam wouldn't have been gone this long. He grabbed his keys.
"I'm going to look for him." Startled Gordon looked up.
"You think it's that serious?"
Dean nodded.
"I do. Something's just not...right. A kind of feeling..."
Gordon nodded.
"I suggest we get a move on than. I'll take my car as well."
Dean nodded. He quickly slid into the Impala and started it, as he started to slowly drive down the street next to the motel, his eyes scanning the sidewalk.
"Come on Sammy," he whispered. "Where the hell are you?"
As soon as the monsters had untied him Sam bolted. He ignored their protesting shouts. He had to escape. Neasuea grew inside of him. His visions were blurred, something was strange. He couldn't see properly. He covered his ears at a door slamming shut. His hearing had also intensified.
Everything was sharper. He shuddered, a sickening realization swept over him as he felt something strange in his mouth. He poked at it. Fangs. He felt sick. Those bastards, those monsters turned him into a Goddamned Vampire.
Bile rose and he bent over and vomitted, over and over again. Vampire...They had turned him into a bloodthirsty monster. The kind that Gordon hunted.
Gordon. Fear flickered in him. In Gordon's eyes there was no grey, there was no black and white. Wouldn't think twice about killing Sam. And Dean...with Gordon manipulating him would Dean be swayed into killing his own brother? Now that Sammy had become one of the things they had hunted?
Fear created a new home inside of him. He started to hypervenilate. His eyes shifted everywhere.
What the hell was he going to do? One thing was for certain. He couldn't go back to Dean. He couldn't go to anyone, not even Bobby. They'd kill him on the spot. He shuddered and swallowed back tears.
He was all alone...A fitting fate for the monster that he had unwillingly become...
To Be continued
