A tough guy goes undercover on a personal mission of vengeance into the hardcore world of S&M, to find out who's responsible for the death of his brother.

Matt Sorenson (Dolph Lundgren), a former boxer and San Francisco cop, now makes a living collecting debts for small businesses. The brutal death of of his high powered younger brother, Michael, changes all that forever. Intent on finding his brother killer, Sorensen infiltrates the powerful inner world of politics, business intrigue and casual sex. Rejecting the police and media theory that the murder is the work of a female prostitute, Sorensen's focus falls on the corrupt big city businessman, Jim Conway. His obsession to discover the killer's identity mounts a a series of other men are found murdered in a similar fashion. Sorensen looses all objectivity and becomes a one man vigilante—anonymous