Robert Lamoureux as Arsène Lupin / Lieutenant André Laroche

Robert Dalban as Inspector Béchoux of the Judicial Police

Alida Valli as Aurélia Valéano

Jacques Dufilho as Albert, manservant

Yves Robert as La Ballu

Roger Dumas as Isidore Bautrelet aka 'Véritaz'

Hubert de Lapparent as French Consul in Florence

Jean Bellanger as Sleeping car employee

Liliane Chenevière as

Michel Etcheverry as Van Nelden, collector

Jean Galland as General

Gisèle Grandpré as Madame du Bois-Lambert

Harold Kay as Henri

Paul Müller as Attaché of the French consulate in Florence

Ginette Pigeon as Agnès, nurse

Anne Valon as

Michel Vocoret as

Gérard Darrieu as Sidekick

Pierre Duncan as (uncredited)

Gabriel Gobin as SNCF employee (uncredited)

René Hell as Prison guard (uncredited)

René Lefèvre-Bel as (uncredited)

Judith Magre as (uncredited)

Claude Mercutio as (uncredited)

Paul Préboist as Drunkard of Enghien (uncredited)

Robert Rollis as Traveler on the train (uncredited)

Paul Villé as Secretary of the archives (uncredited)