The "Stone Killer" of underworld argot is a particularly cold-blooded and ruthless character -- on either side of the law. An as a tough, dedicated plainclothes cop waging war against the evils of society with a ruthlessness that could make him as much at home on the side of the criminals he pursues as he is with the law, Torrey (Charles Bronson) is just such a man. Assigned by Detective Captain Daniels (Norman Fell) to assist Torrey is Mathews (Ralph Waite), a bungling bigot whose problems are compounded by the trouble he has communicating with his beautiful teenaged daughter (Christina Raines). Chief among Torrey's enemies is the mob tycoon Vercari (Martin Balsam). To track him down, Torrey must travel from the seamy underworlds of New York's Spanish Harlem and Little Italy, to the Skid Row of Los Angeles. But it's in the idyllic world of Southern California's Topanga Canyon where he meets Gerry Wexton (Kelly Miles), an airline stewardess convicted of a bad check charge who has left conventional society to live in a psychedelic commune.