Elenco - The Madman of Lab Four
Jean Lefebvre
Eugène Ballanchon, scientific researcher, single
Maria Latour
Régine, Mr. Beauchard's spy
Bernard Blier
Mr. Beauchard, executive secretary linked to a gang
Michel Serrault
Mr. Granger, director of the scientific laboratory
Pierre Tornade
DST inspector
Pierre Brasseur
Father Ballanchon
Margo Lion
Mrs. Ballanchon, Eugène's mother
Robert Dalban
Merchant, spy in the laboratory
Mario David
Mario
Paul Préboist
Police officer
Henri Virlogeux
Scholar
André Chaumeau
Baron
Jean Franval
DST inspector
Alain Janey
Fred
Sabine Sun
Baroness
Yvon Sarray
PedestrianMax Arian
Extra worker (uncredited)
André Cagnard
Jo (uncredited)
Guy Delorme
Actor from the western (uncredited)
Marius Gaidon
Police officer (uncredited)
Henri Guégan
Actor from the western (uncredited)
Jean Ozenne
Minister (uncredited)
Laure Paillette
Traveler (uncredited)
Lionel Vitrant
Actor from the western (uncredited)