Jean Dujardin

Picquart

Louis Garrel

Alfred Dreyfus

Emmanuelle Seigner

Pauline Monnier

Grégory Gadebois

Henry

Hervé Pierre

General Gonse

Wladimir Yordanoff

General Mercier

Didier Sandre

General Boisdeffre

Melvil Poupaud

Maître Labori

Eric Ruf

Sandherr

Mathieu Amalric

Bertillon

Laurent Stocker

General de Pellieux

Vincent Perez

Maître Leblois

Michel Vuillermoz

Du Paty de Clam

Vincent Grass

General Billot

Denis Podalydès

Maître Demange

Damien Bonnard

Desvernine

Laurent Natrella

Esterhazy

Bruno Raffaelli

Judge Delegorgue

Christophe Maratier

Warrant Officer

Stefan Godin

General Darras

Yannik Landrein

Gast

Luca Barbareschi

Philippe Monnier

Fred Epaud

Artillery Officer

Nicolas Wanczycki

Foucault

Franck Mercadal

Captain Calmont

Philippe Magnan

Attorney Brisset

Édith Le Merdy

Concierge

Jeanne Rosa

Martha Leblois

Benoît Allemane

Georges Charpentier

André Marcon

Émile Zola

Jean-Marie Frin

Judge Delegorgue

Brigitte Boucher

Marie Bastian (uncredited)

Michèle Clément

Washerwoman (uncredited)

Nicolas de Lavergne

Auguste Dutrieux (uncredited)

Roman Polanski

Concertgoer (uncredited)