Jojo’s ambition is to become a gangster, but to be admitted into a gang he has to prove himself by committing a daring act. To that end, he kills someone in broad daylight, not knowing that his victim is an actor who is playing a scene in a film directed by a cranky film-maker (Darry Cowl). The murder is caught on film, leading Commissaire Bernard (Michel Simon) to think that the killer will be easy to find. Sure enough, Bernard soon makes his arrest, a clown from a circus, but then he faces an almost insurmountable problem. The clown has an identical twin, who is also a clown with the same circus. Both men claim to be innocent…