在这部变色龙惊悚片中,威利具有“变色龙”的超强本事。所以当政府需要一个人做卧底调查黑帮军火交易时，他就成了最佳的人选。他摇身一变，接连化成了几个不同的角色：监狱里十恶不赦的犯人托尼，考·迪西公司里的审计员赛特，狼狈不堪的流浪汉等。而考·迪西正是多年前杀害他妻子的仇人！为了报仇，他故意接近公司里漂亮的赫曼小姐，却发现自己爱上了她……但强烈的复仇欲望使他没忘记自己的任务，最终他查出了考·迪西一伙贩卖武器和毒品的底细，并在一场搏斗中杀死了考·迪西，而“变色龙”的本性也让威利精神崩溃。
A government agent who had retired comes out to try to find a druglord who had his family murdered. However, as he assumes various roles, his chief becomes concerned about him as he starts struggling to differentiate between reality and his make-up.
