Lieutenant Jacob 'Jake' Beser
Lucy Tibbets
Colonel Paul Tibbets
Major Tom Ferebee
Captain Bob Lewis
Major Wiiliam 'Bud' Uanna
Sergeant Shug Crawford
Captain William 'Deke' Parsons
Field Marshall Abehata
J. Robert Oppenheimer
Alexander Sachs
General Groves (as Richard T. Herd)
Secretary of War Stimson
President Harry S. Truman
Lieutenant Tatsuo Yamato
Aya
Capt. Theodore 'Dutch' Van Kirk
Captain Claude Eatherly
President Franklin D. Roosevelt
General George Marshall
(as Matthew McGowan)
(as Dick Christie)
General Nagai
Airman
MP (as Kirk I Koskella) (credit only)
(as Stephen Keep)
Sweeney
Radio Operator
General Curtis LeMay
Sign Painter (uncredited)
excited Airman (uncredited)
Officer Giving Camera to Tailgunner (uncredited)