Obsazení
Tony Shalhoub
Enrico Fermi
John Seitz
Ralph A. Bard
Lorne Brass
Klaus Fuchs
Dee McCafferty
William 'Deke' Parsons
David Ferry
Army Major
Barnard Hughes
Henry Stimson
Anne Twomey
Kitty Oppenheimer
David Ogden Stiers
Franklin D. Roosevelt
Michael Sinelnikoff
Lord Rutherford
Harry Standjofski
Robert Wilson
Tom Butler
Captain DeSilva
Romano Orzari
Leo Szilard's Prime Scientist (uncredited)
Hal Holbrook
Gen. George Marshall
Vlasta Vrana
Hans Bethe
Lia Sargent
Mrs. Wisnovsky
Arthur Holden
Scientist (uncredited)
Lawrence Dane
David Gow
Jack Wisnovsky
Heinar Piller
Fleischmann
Ron White
Colonel Nichols
Jonathan Wise
Robert Serber
David Strathairn
J. Robert Oppenheimer
Richard Dysart
President Harry S. Truman
Ron Frazier
Colonel Pash
Bernie McInerney
Timothy Webber
Colonel Lansdale
Michael J. Reynolds
Kenneth Bainbridge
Roland Hewgill
Army General
Olek Krupa
Edward Teller
Isabelle Mejias
Mrs. Trowbridge
Hume Cronyn
James F. Byrnes
John McMartin
Dr. Arthur Compton
George R. Robertson
Ed Condon
Ken Pogue
Dwight D. Eisenhower
Alan Scarfe
Patrick Breen
Richard Feynman
Gary Reineke
Groves's Commanding Officer
Brian Dennehy
Gen. Leslie Groves
Scott Thomson
Chemist
Michael Tucker
Leo Szilard