Professor Charles Buisson, astronomer and Nobel Prize winner, has just discovered a nova. He informs the other observatories by telephone. Just as he thinks one of them is calling back, he finds himself on the line with a young woman threatening suicide at the Ruban Bleu cabaret, if her lover hasn't joined her by midnight. Intrigued, the professor decides to go and prevent the unfortunate woman from committing suicide. One of his students, who earns her living as an understudy in a knife act, helps him in his investigation, while the school principal and a policeman suspect him of being a prankster or even of selling drugs. For the scientist, it's an opportunity to discover a world of music-hall that he'd never known before: "I thought I knew the sky chart by heart, but there's one planet that was totally unknown to me: Earth. I'll be back!
as Professor Charles Buisson
as Gisèle, student of Buisson
as Lucien Mosca, boss of Ruban Bleu
as Mrs. Rédéri
as The determined trafficker
as Pierre-Dominique, aka 'Pépé'
as Maurice, Buisson's assistant
as Patrice
as Mrs. Buisson
as Henriette, washroom attendant
as The indecisive snob
as Russian Princess
as Woman from Paris
as Poupette, presenter of the show
as Woman from Paris
as Woman from Paris
as Woman from Paris
as Woman from Paris
as Woman from Paris
as Woman from Paris
as Cloakroom attendant
as Florist
as Inspector Corbin
as Self
as Self
as Self
as Self
as Self
as Self
as Narrator
as Magda, the pregnant dancer (uncredited)
as Cowboy (uncredited)
as Young female client of Ruban Bleu (uncredited)
as Self (uncredited)
as Self (uncredited)
as Policeman at Quai des Orfèvres (uncredited)
as Arsène the toothless (uncredited)
as Woman with stomach ache (uncredited)
as Police officer (uncredited)
as Young customer of Ruban Bleu (uncredited)
