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
Margo Lion
Mrs. Ballanchon, Eugène's mother
Robert Dalban
Merchant, spy in the laboratory