Charles Dreyfus, former chief inspector of the French Surete, has been cleared for release from a mental hospital when the man who caused his breakdown in the first place, the bumbling Chief Inspector Clouseau, visits him in the hospital with good intentions and restores him to insanity. Dreyfus escapes the hospital, vowing to kill Clouseau.
Working alone, the obsessive Dreyfus tries numerous times to kill Clouseau, but is unsuccessful, so he adopts a new strategy: kidnapping a renowned scientists, recruiting the world's top assassins, and beginning the construction a machine that can destroy the world. Dreyfus threatens to begin obliterating cities if Clouseau is not delivered to him.
Despite the threats and the efforts of the assassins, Clouseau is continually saved by his own incompetence, and after thwarting numerous attempts on his life, he goes on a solo mission to find Dreyfus, capture him, and return him to the authorities.