After a performance at the Concert Mayol, a Parisian music hall, dancer Mado is poisoned with arsenic and transported to hospital, and survives. Immediately the rumors run behind the scene.
At the Concert Mayol, which features lavish striptease shows, Mado, the star, drinks poison in a glass of champagne used in a production number and is rushed to the hospital, where her life is saved. Some time later, however, Mado's understudy, Lydia, is found shot while wearing one of Mado's costumes. Inspector Million is brought in and after numerous embarrassing experiences he realizes that the murderer was after Lydia all the time. The director of the show, who recently quarrelled with Lydia, comes under suspicion, as does Fred, a narcotics dealer and pimp with whom she has been having an affair. Soon the evidence against Max, Mado's lead signer and current lover, builds up in spite of his efforts to incriminate Bob, Lydia's protector. Although Max eludes the police, Bob eventually captures him.
