A Stranger Within (2003)

Released after five years of institutionalization for a crime he doesn't remember committing, Danny, with the body of a man and the mind of a child, lives in the care of his older brother, Bill. Bill's increasingly bizarre behavior goes unnoticed by Danny, who is preoccupied with the fear of being separated from him by the growing demands of Bill's girlfriend, Sarah. Danny is further distracted by a newfound attraction to Suzy, a woman with her own questionable past. As Bill further succumbs to a descent into deviance, his actions threaten himself and those around him. Will Danny finally awaken to the truth of his own forgotten past and Bill's inner demons and be able to stop him before it's too late?