墨菲威尔森(杜夫朗格饰)是个拳击手兼旧金山的警探,如今却沦为替小企业讨债过生活,而他位高权重的弟弟麦克伦惨死,使他的生活瞬间改变,威尔森企图找出杀弟的凶手,因此回到了故乡追查凶手,并计划潜入政经阴谋和情欲纠葛的黑社会,威尔森发现杀弟凶手是个从事卖淫事业心狠手辣的家伙,且政商关系良好,为了对付凶手,威尔森全然失去了理性,变成了一个可怕的杀人狂…… 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