Diamonds Are Brittle

Jean Seberg

Bettina Ralton

Claude Rich

Bernard Noblet

Elsa Martinelli

Juliette

Elisabeth Flickenschildt

Madame Ralton

Günther Jerschke

Goretti

Ady Berber

Max

Walter Roderer

Cuendet

Pierre Vernier

Roger

Jacques Morel

Amédée de St. Leu

Jean-Paul Moulinot

Jeweler

Jacques Balutin

Agent

France Rumilly

Lady with the ring

Daniel Ceccaldi

Captain of the boat

Claude Darget

Cantonal inspector

Henri Virlogeux

Picard

Annette Poivre

Cleaning lady

Jacques Dynam

Commissioner

Pierre Mirat

Brigadier

Jean-Pierre Rambal

Policeman

Jacques Santi

Traveler at the airport

Norma Dugo

Cleaning lady

Michel Danjou

Bernard Musson

Policeman

Yves Arcanel

Louis Viret

Policeman

Paul Pavel

Brigadier

Marcel Gassouk

Brigadier

Günter Lüdke

Marcellino

Horst Pasderski

Werner Schwier

Dr. Worms

Günther Ungeheuer

Prof. Schmoll

Marcel Charvey

Ducret, member of the billiards club (uncredited)

André Dalibert

Policeman at the police station (uncredited)

Yves Elliot

Cantonal inspector (uncredited)

Marius Gaidon

Policeman at the police station (uncredited)

Max Melder

(uncredited)

Gaston Meunier

Man in the toilet (uncredited)

Laure Paillette

Cleaning lady (uncredited)

Jacques Préboist

Employee at the airport (uncredited)