Bob Letellier, a good looking rich kid who studies science, makes the acquaintance of Alain, a cynical and immoral young man. The latter introduces him to the existentialist circles of Saint-Germain-des-Prés. Bob is invited to a party and becomes Clo's lover, a rich heiress.
Jacques Charrier
as Robert 'Bob' Letellier
Pascale Petit
as Mic
Andréa Parisy
as Clotilde de Vaudremont
Laurent Terzieff
as Alain
Roland Lesaffre
as Roger
Pierre Brice
as Bernard
Jean-Paul Belmondo
as Lou
Dany Saval
as Nicole
Denise Vernac
as La mère de Mic
Jacques Marin
as Hippolyte Félix
Jacques Perrin
as le jeune qui monte sur la Vespa
