The moment that the two Winchester brothers had been fearing had finally come to past. They both had fought it, ignored it, even denied its possibility of actually happening; but it took place just the same. Sam had turned. All the good inside of him wiped out in a second, the essence that made him Sam Winchester, Dean's beloved little brother, had been replaced by something beyond recognition. Dean had watched it happen; he had seen the exact moment when something inside Sam shifted, releasing the darkness and fury within, bringing Dean's worst nightmare to life.
Sam had held the possessed man's head under in a bucket of holy water, his face perspiring from the steam that engulfed it as the demon gripped in his hands kicked and flailed against the burn of the sanctified liquid against its skin. He had tortured the demon for the information he needed, leaving the body of thepossessedextremely broken and bleeding. Dean had watched and interfered on the occasion when Sam got too vigorous in his interrogation, reminding him of the innocent person trapped inside. Sam simply shrugged off Dean's warning and continued reading the Latin words from the exorcism listed in their Father's leather-bound journal.
Finally the exorcism was finished, the demon expelled from the innocent man's body and into the protective circle above, leaving him slumped over and gasping in pain. Dean rushed to the man, checking the severity of his injuries and speaking soft words of comfort. Dean was working on untying his left arm when he heard a gunshot. A bullet flew past him, mere inches from his head, and hit the newly-freed man in the chest. Dean jumped back in shock as another shot sounded from the gun clutched in Sam's hand, hitting the man in the right shoulder.
"Sam!" Dean was on his feet in a second and running at Sam, tackling him to the ground right after he fired a third bullet into the now-dead man. The brother's fell to the floor with a thud, fighting for the gun.
"Sam! What the hell are you doing?!?!" Dean finally managed to wrestle the gun from his brother's grip and toss it out of reach. Sam smirked at Dean and threw him clear across the room, crashing him hard against a wall; a feat a regular man could normally never accomplish. Dean gasped as the air flowed back to his lungs. His head swam and his vision crossed in and out of focus as he looked up at Sam, who was now standing over him.
"S-Sammy?" Dean gasped breathlessly, his heart beating fast within his heaving chest.
Sam raised his hand, palm facing up toward the ceiling. Dean felt an invisible force pull him to his feet and press him against the wall. Dean searched the face of the person in front of him, confused and stricken with panic at the strangely unfamiliar eyes that stared back at him. Sam's lips twisted down into an angry frown. His voice was deep and even as he spoke through clenched teeth.
With another quick movement of his hand, Sam bashed Dean's head against the wall with crushing force. He released his invisible hold after a moment, allowing Dean to fall heavily to the floor, unconscious.
That had been a month ago, and Dean hadn't heard from or seen his brother since.