In a moment of madness a middle-aged, married and respectable pharmacist kills a young woman who is sun-bathing by a lake. Unable to take in what he has done, he flees from the scene of the crime and behaves as if nothing has happened. Eventually her boyfriend is charged with the crime and, in a strange twist of fate, the killer finds himself serving on the jury.

Bernard Blieras Grégoire Duval pharmacien
Maurice Biraudas Le docteur Hess - le vétérinaire
Francis Blancheas Le procureur général
Danièle Delormeas Geneviève Duval
Jacques Riberollesas Sylvain Sautral, photographe et accusé
Yves Barsacqas Maître Adreux - l'avocat de la défense
Henri Crémieuxas Le médecin légiste
Robert Dalbanas Garampon -le pêcheur sur sa barque
Anne Doatas Alice Moreux
Madeleine Geoffroyas Mme Sevestrain
Maurice Fellous