In the elevator of two large Parisian buildings, a telegraph operator discovers the body of an elderly woman, Madame Mathieu, the owner of both buildings. Boucheron, the local superintendent, is dispatched to investigate, along with his rival, Inspector Lambert of the "Sûreté". To solve the enigma, they scour staircases and corridors, visiting every floor of both buildings, courtyard and facade. Their gruff rivalry allows them to complement each other in discovering who committed the crime among a gallery of characters, humble or rich, who all have something to be ashamed of... A rare, fast-paced, picturesque comedy set against the backdrop of a police mystery.
Lucien Baroux
Commissioner Boucheron, district police officer
Jacques Baumer
Inspector Lambert of the Sûreté
Jules Berry
Alfredo d'Avila, dancer of these ladies
Gaby Morlay
Gaby Valrose, minister's lover
Elvira Popescu
Mrs. Rameau, wife of an industrialist and mistress of Alfredo
Michel Simon
Picking, knife-throwing artist
André Lefaur
Mr. Corbeau, kleptomaniac
Gaby Sylvia
Madeleine Martin, in love with André
