O.S.S.

Alan Ladd

as John Martin / Lt. (j.g.) Philip Masson, U.S.N.R. / Philippe Martine

Geraldine Fitzgerald

as Miss Ellen Rogers / Madame Elaine Duprez

Patric Knowles

as Cmdr. Brady

John Hoyt

as Col. Paul Meister

Gloria Saunders

as (W)omen's (A)rmy (C)orps Radio Operator Mary

Richard Webb

as Frank Schmidt (O)perational (S)upport (P)ackages, (M)aterial, Maintenance, Management, U.S.N.R. / Parker

Richard Benedict

as Robert Bouchet, Tech Sgt., A.U.S. / Albert Bernardi

Harold Vermilyea

as Amadeus Brink

Don Beddoe

as Rodney "Gates" Parrish / Raoul Josse

Onslow Stevens

as Field

Gavin Muir

as Col. Crawson

Egon Brecher

as Marcel Aubert

Joseph Crehan

as Gen. Donovan

Bobby Driscoll

as Gerard

Julia Dean

as Madame Prideaux

Crane Whitley

as Arnheim

Dorothy Adams

as Claudette (uncredited)

John Dehner

as German Radar Captain (uncredited)

Frank Ferguson

as Electronics Engineer (uncredited)

Leo Schlesinger

as German Soldier (uncredited)

Carl R. Botefuhr

as American Soldier (uncredited)

George Bruggeman

as MP NCO (uncredited)