- Walter Huston
- Ambassador Joseph E. Davies
- Ann Harding
- Mrs. Marjorie Davies
- Oscar Homolka
- Maxim Litvinov, Foreign Minister
- George Tobias
- Freddie
- Gene Lockhart
- Premier Molotov
- Eleanor Parker
- Emlen Davies
- Richard Travis
- Paul
- Helmut Dantine
- Maj. Kamenev
- Victor Francen
- Vyshinsky, chief trial prosecutor
- Henry Daniell
- Minister von Ribbentrop
- Barbara Everest
- Mrs. Litvinov
- Dudley Field Malone
- Winston Churchill
- Roman Bohnen
- Mr. Krestinsky
- Maria Palmer
- Tanya Litvinov
- Moroni Olsen
- Col. Faymonville
- Minor Watson
- Loy Henderson
- Vladimir Sokoloff
- Mikhail Kalinin, USSR president
- Maurice Schwartz
- Dr. Botkin
- Joseph E. Davies
- Joseph E. Davies - in Prologue
- Ernst Hauessermann
- Ship's Steward
- John Abbott
- Grinko
- Ernie Adams
- Heckler
- Ed Agresti
- Second Trial Judge
- Alex Akimoff
- O.G.P.U. Man
- Fred Aldrich
- Man at Bar in Montage
- Demetrius Alexis
- O.G.P.U. Man
- Elizabeth Archer
- Elderly Woman
- Louis V. Arco
- Train Announcer
- Sam Ash
- American Senator
- Herbert Ashley
- Electrician at Madison Square Garden
- Hooper Atchley
- Father
- Robert Baikoff
- Soldier
- Felix Basch
- Dr. Hjalmar Schacht - Banker
- Nino Bellini
- Italian Reporter
- Ted Billings
- Man at Inn
- Tina Blagoi
- Russian Woman
- Oliver Blake
- Heckler
- Monte Blue
- Heckler
- Eugene Borden
- M. Delbeau - French Minister
- Egon Brecher
- Heinrich Sahm
- Barbara Brown
- Well-Wisher at Train
- Morgan Brown
- American Delegate
- Alexander Campbell
- Senator
- George M. Carleton
- Congressman
- James Carlisle
- American Senator
- Maurice Cass
- Yugoslavian President
- Nikolai Celikhovsky
- Soviet Official
- Feodor Chaliapin Jr.
- Shop Foreman
- Luke Chan
- Japanese Diplomat
- Cyd Charisse
- Galina Ulanova - Ballerina
- Jack Chefe
- Newspaperman in Courtroom
- Alex Chivra
- Pierre Laval
- Peter Chong
- Japanese Ambassador Shigemitsu
- Virginia Christine
- Maria - Beautician
- Winston Churchill
- Winston Churchill
- Wallis Clark
- Well-wisher with Bill
- Donald Clayton
- Vincent Massey
- Edmund Cobb
- Heckler
- James Conaty
- Dinner Guest
- Harry Cording
- Blacksmith
- Gino Corrado
- Italian
- Jerome Cowan
- Spendler
- Noel Cravat
- Workman
- Joseph Crehan
- Reporter
- Oliver Cross
- Delegate Van deWater
- Albert D'Arno
- Frenchman
- Jacqueline Dalya
- Russian Girl
- William B. Davidson
- Senator
- George Davis
- French Reporter
- Jean De Briac
- French Maniac
- Leander De Cordova
- Heckler
- Wally Dean
- Isolaltionist
- Igor Dega
- Litvinov's Secretary
- Jean Del Val
- Molotov's Secretary
- Lala Detolly
- Russian Woman
- John Dilson
- American Senator
- Warren Douglas
- Emlen's Well-Wisher at Train Station
- George Du Count
- O.G.P.U. Man
- Eugene Eberle
- Son
- Oliver Eckhardt
- Radio Listener
- Anthony Eden
- Anthony Eden
- Ben Erway
- Heckler
- Fred Essler
- Dutch Banker
- Herbert Evans
- Courtroom Spectator
- Adolph Faylauer
- German Diplomat at Train Station
- Frank Faylen
- Reporter
- Frank Ferguson
- American Newsman
- Robert Fischer
- von Schulenberg
- James Flavin
- American Senator
- Ray Flynn
- Isolationist
- Lee Tong Foo
- Tsiang Ting Fu - Chinese Ambassador
- Ross Ford
- Johnny - Emlen's Well-Wisher at Train Station
- William Forrest
- American Newsman
- Patrica Fung
- Chinese Girl
- Jack Gardner
- Newsreel Photographer
- Gene Gary
- Russian Foreman
- Art Gilmore
- Commentator
- Joseph W. Girard
- American Senator
- Sam Goldenberg
- Mr. Leon Trotsky
- Ernest Golm
- Fat German
- Lisa Golm
- Train Passenger Arriving Late
- Gregory Golubeff
- Commandant of the Court
- Christine Gordon
- Parachutist
- William Gould
- Isolationist
- Alexander Granach
- Russian Air Force Officer
- Jesse Graves
- White House Butler
- Henry Guttman
- O.G.P.U. Man in Taxi
- Hermann Göring
- Self
- Bobbie Hale
- Man at Inn
- John Hamilton
- Charlie - American Newsman
- Lumsden Hare
- Lord Chilston
- Sam Harris
- Parade Spectator
- Henry Hebert
- Isolationist
- Frank Hemphill
- Grandfather
- Yvonne Hendricks
- Minister's Wife
- Louis Jean Heydt
- American Newsman
- Herbert Heyes
- Congressman
- Adolf Hitler
- Adolph Hitler
- David Hoffman
- Mr. Radek
- Mauritz Hugo
- Heckler
- Olaf Hytten
- Parliament Member
- Frieda Inescort
- Madame Molotov
- Ted Jacques
- Machinist
- Frank Jaquet
- Dutch Banker
- Allen Jung
- Japanese Diplomat
- Erwin Kalser
- German Businessman
- Joseph Kamaryt
- Old Russian
- Eddie Kane
- Heckler
- Zoia Karabanova
- Russian Train Engineer
- Kurt Katch
- Gen. Semen Timoshenko
- Edward Keane
- Isolationist
- Kenner G. Kemp
- Newspaperman
- Bill Kennedy
- American Newsman
- Jack Kenney
- Heckler
- Colin Kenny
- Parade Soldier Spectator
- Emmett King
- British Delegate
- Manart Kippen
- Joseph Stalin
- Nicholas Kobliansky
- O.G.P.U. Man
- Al Kunde
- Father
- Adia Kuznetzoff
- O.G.P.U. Man
- Charles La Torre
- Rosso - Italian Ambassador
- Charles Lane
- Man in Kitchenin Montage
- Ivan Lebedeff
- Mr. Rosengoltz
- Gabriel Lenoff
- O.G.P.U. Man
- George Lessey
- Bill - Well-wisher
- Marion Lessing
- Telephone Operator
- Carl M. Leviness
- Reporter
- Adolf E. Licho
- Bookseller
- Rolf Lindau
- German Reporter
- Doris Lloyd
- Mrs. Churchill
- Kathleen Lockhart
- Lady Chilston
- Arthur Loft
- Man with Microphone
- Wilbur Mack
- American Newsman
- Rosa Margot
- Russian Servant
- Michael Mark
- Timid Man
- Janet Martin
- Natasha
- John Maxwell
- Reporter at Train
- Mike Mazurki
- Russian Machinist Workman
- Lafe McKee
- Radio Listener
- Frank McLure
- League of Nations Official / Ball Guest (uncredited)
- Alex Melesh
- Mr. Pyatakov
- Marie Melesh
- Young Woman
- Tina Menard
- Telephone Operator
- Peter Michael
- German Reporter
- Harold Miller
- Dancer at Ball / Congressman (uncredited)
- Howard M. Mitchell
- Heckler
- Vyacheslav Molotov
- Vyacheslav Molotov
- Clive Morgan
- Anthony Eden
- Forbes Murray
- Isolationist
- Martin Noble
- Russian Officer
- Barry Norton
- Ball Guest
- Field Norton
- Congressman
- Alex Novinsky
- Courtroom Reporter
- Pat O'Malley
- Irish-American in Montage
- Daniel Ocko
- Mr. Yagoda (former OGPU Head)
- Michael Panaieff
- Ulanova's Dancing Partner
- Paul Panzer
- Court Attendant
- Emory Parnell
- Uncaring Businessman
- Manuel ParÃs
- Russian Military Policeman
- Irene Pedrini
- Telephone Operator
- Frank Penny
- Heckler
- Francis Pierlot
- Doctor
- René Plaissetty
- Coulendre
- Frank Puglia
- Trial Judge Ulrich
- Louis Quince
- Member of Parliament
- Emil Rameau
- Ignacy Paderewski
- Frank Reicher
- General von Koestrich - German ambassador
- Duncan Renaldo
- Italian Reporter
- Georges Renavent
- President Paul van Zeeland
- Vera Richkova
- Parachutist
- Betty Roadman
- Mother
- Constantine Romanoff
- Accused Member of O.G.P.U.
- Nico Romoff
- Foreman
- Lionel Royce
- Herr Schmidt
- Richard Ryen
- German Major
- Loulette Sablon
- Telephone Operator
- Tanya Samova
- Flower Girl
- Sam Savitsky
- Spadebeard
- Ferdinand Schumann-Heink
- German Reporter
- Hans Schumm
- Train Gate Guard
- Irina Semochenko
- Parachutist
- Konstantin Shayne
- Mr. Nikolai Bukharin
- Robert Shayne
- Engineer
- Tamara Shayne
- Russian Nurse
- Evelynne Smith
- Daughter
- Leonid Snegoff
- Kommodov
- George Sorel
- German Bund Member
- Joseph Stalin
- Joseph Stalin
- Rudolf Steinboeck
- German
- Glenn Strange
- Southerner in Montage
- Mark Strong
- Englishman
- Sándor Szabó
- Ski Troop Lieutenant
- Ben Taggart
- Guest at Davies' Speech
- Mike Tellegen
- O.G.P.U. Man
- Zina Torchina
- Parachutist
- Ivan Triesault
- Mr. Tukhachevsky (Former General)
- Charles Trowbridge
- Secretary of State Cordell Hull
- Tom Tully
- American Engineer in Russia
- Olga Uljanovskaja
- Russian Nurse
- Edward Van Sloan
- German Diplomat in Berlin
- Henry Victor
- Herr Schufeldt - Hamburg Official
- Michael Visaroff
- Barkov
- Ray Walker
- Raymond - Davies' Butler
- Glen Walters
- Mother
- Pierre Watkin
- Naval Attache
- Peggy Watts
- Telephone Operator
- Frank Wayne
- Heckler
- John Wengraf
- Polish Ambassador Grzybowski
- Mischa Westfall
- Petya
- Leigh Whipper
- Haile Selassie
- Marek Windheim
- Mr. Sokolnikov
- Joan Winfield
- Telephone Operator
- Isabel Withers
- Well-Wisher at Train
- Jean Wong
- Parachutist
- Victor Wong
- Japanese Diplomat
- Katherine Yorke
- Russian Woman
- Jack Young
- President Roosevelt
- Alfred Zeisler
- German Train Conductor
- Esther Zeitlin
- Russian Woman
