In retaliation for the death of his son, a big-time hoodlum hires an expert female assassin known as Sydney to murder the three thugs responsible. At the same time, SFPD detective Keller (Michael Douglas) becomes romantically involved with his attractive new neighbor (played by Douglas' then-girlfriend Brenda Vaccaro. In this case, the viewer is way ahead of the detective: Keller's sweetheart is none other than the elusive Sydney. ~ Hal Erickson, Rovi