Dalton Trumbo
Edward G. Robinson
Rocco (as Dave Maldonado)
Sam Wood
Cleo Trumbo
Party Goer
Hedda Hopper
John Wayne
Chris Trumbo (age 6-10) (as Tobias McDowell Nichols)
Rally Participant
Niki Trumbo (age 8-11)
Young Father
J. Parnell Thomas
Ian McLellan Hunter
Arlen Hird
Roy Brewer
Louis B. Mayer
Buddy Ross
Robert Stripling
Reporter
Robert Kenny
Jury Foreman
Jeff Krandall
Prison Guard (as John E. Moore)
Prison Guard (as PJ Marshall)
Virgil Brooks
Mitzi Trumbo (age 6-8)
Chris Trumbo (age 10-12)
Niki Trumbo
Frank King
Hymie King
Mover
Next Door Neighbor
Messenger (as AJ Allegra)
Chris Trumbo (age 13-17) (as Matthew Liptak)
Mitzi Trumbo (age 9-12)
Kirk Douglas
Andrew Hird
Niki's Friend
Journalist
Otto Preminger
Edward 'Ed' Muhl
TV Interviewer
President John F. Kennedy
DC Reporter
Master of Ceremonies
Chris Trumbo (age 29)
Irving Radovich in Roman Holiday (archive footage) (uncredited)
Writers Guild Member (uncredited)
Prisoner (uncredited)
Self (archive footage) (uncredited)
Self (voice) (archive footage) (uncredited)
Congressman (uncredited)
Starlet (uncredited)
Waiter (uncredited)
Backyard Reporter (uncredited)
Police officer (uncredited)
News Reporter (uncredited)
Hearing Attendee / American Legion Member (uncredited)
Legionaire / Banquet Attendee (uncredited)
News Reel Voice Overs (voice) (uncredited)
Adrian Scott (uncredited)
News Reporter / American Legion (uncredited)
Maitre d (uncredited)
D.C. Courtroom Bailiff (uncredited)
Movie Theatre patron (uncredited)
Studio Executive (uncredited)
U.S. Marshall #2 (uncredited)
Theatre Goer / Protester (uncredited)
Princess Ann (archive footage) (uncredited)
Japanese Soldier (uncredited)
Older Man at Funeral (uncredited)
Older Woman at Funeral (uncredited)
Vivacious Receptionist (uncredited)
News Reporter / Photographer / American Legion (uncredited)
Journalist (uncredited)
Ethel (uncredited)
Starlet / Premiere Attendee (uncredited)
Showgirl (uncredited)
Trumbo Friend (uncredited)
Party Guest (uncredited)
Niki's Friend (uncredited)
Trumbo Neighbor (uncredited)
Private Eye / Banquet Guest (uncredited)
Busboy (uncredited)
Gladys Robinson (uncredited)
Marty (uncredited)
Hunter's Son (uncredited)
Prison Guard (uncredited)
Crassus (archive footage) (uncredited)
Joe Bradley (archive footage) (uncredited)
EGR friend / Air field cop / clerk (uncredited)
Assistant chief investigator (uncredited)
Albert Maltz (uncredited)
Limo Driver (uncredited)
Premiere Attendee / Reporter / Banquet Attendee (uncredited)
Enlisted Man (uncredited)
Warden (uncredited)
Young studio executive (uncredited)
Ross's Girlfriend (uncredited)
Concession Stand Lady / Spartacus Premiere Attendee (uncredited)
Varinia (archive footage) (uncredited)
Juror (uncredited)
Make-up Artist (uncredited)
Draba (archive footage) (uncredited)
Laugher (uncredited)
John (uncredited)
Blacklist Member (uncredited)
Actor (uncredited)
Alvah Bessie (uncredited)
Poolside bartender (uncredited)
Roman Senator (uncredited)