Jean Lefebvre as Eugène Ballanchon, scientific researcher, single

Maria Latour as Régine, Mr. Beauchard's spy

Bernard Blier as Mr. Beauchard, executive secretary linked to a gang

Michel Serrault as Mr. Granger, director of the scientific laboratory

Pierre Tornade as DST inspector

Pierre Brasseur as Father Ballanchon

Margo Lion as Mrs. Ballanchon, Eugène's mother

Robert Dalban as Merchant, spy in the laboratory

Mario David as Mario

Henri Virlogeux as Scholar

André Chaumeau as Baron

Jean Franval as DST inspector

Paul Préboist as Agent

Alain Janey as Fred

Sabine Sun as Baroness

Yvon Sarray as Pedestrian

Max Arian as Extra worker (uncredited)

André Cagnard as Jo (uncredited)

Guy Delorme as Actor from the western (uncredited)

Marius Gaidon as Police officer (uncredited)

Henri Guégan as Actor from the western (uncredited)

Jean Ozenne as Minister (uncredited)

Laure Paillette as Traveler (uncredited)

Lionel Vitrant as Actor from the western (uncredited)