Paul Newman character Gen. Leslie R. Groves
Dwight Schultz character J. Robert Oppenheimer
Bonnie Bedelia character Kitty Oppenheimer
John Cusack character Michael Merriman
Laura Dern character Kathleen Robinson
Ron Frazier character Peter de Silva
John C. McGinley character Capt. Richard Schoenfield, MD
Natasha Richardson character Jean Tatlock
Ron Vawter character Jamie Latrobe
Michael Brockman character William 'Deke' Parsons
Ed Lauter character Whitney Ashbridge
