On the edge of the California desert, an outlaw gang of motorcyclists led by the psychopathic Anchor brutally assaults and murders two young lovers. Later, the gang barges into a remote cafe where Charles and Nora Baldwin, a vacationing policeman and his wife, are dining with Johnny Martin, a hitchhiking Vietnam veteran. When cafe owner Lew insults Anchor's girl friend, Gina, the cyclists knock out Johnny and kill Lew and the Baldwins. Johnny regains consciousness and utilizes his combat training by smashing a mirror in the face of one of the thugs and drowning another in a toilet bowl. Johnny and the cafe waitress, Tracy Stewart, then flee into the desert in the young girl's dune buggy. Forced to abandon the buggy because of a broken gas tank, they proceed on foot until they reach a small natural cave. Meanwhile, the cyclists encounter a group of college girls on a field trip and rape and then murder them after dropping LSD in their coffee. Gina destroys herself by driving her motorcycle over a cliff after Anchor informs her that he is looking for a new girl friend. Johnny manages to kill two other members of the gang and then mistakenly kills Firewater, Anchor's Indian friend who had become disgusted with the leader's lunacy and attempted to help the runaways. Anchor finally overtakes Johnny and Tracy as they are heading toward town, but as the deranged biker hurdles toward them on his cycle, Johnny stops Anchor by hurling a knife into his neck.
