Day One

Hungarian physicist Leo Szilard leaves Europe, eventually arriving in the United States. With the help of Einstein, he persuades the government to build an atomic bomb. The project is given to no-nonsense Gen. Leslie Groves who selects physicist J. Robert Oppenheimer to head the Los Alamos Laboratory in New Mexico, where the bomb is built. As World War II draws to a close, Szilard has second thoughts about atomic weapons, and policy makers debate how and when to use the bomb.

Full Cast of Day One

Brian Dennehy

as Gen. Leslie Groves

Brian Mannion Dennehy (July 9, 1938 - April 15, 2020) was an American actor of film, stage and screen.

David Strathairn

as J. Robert Oppenheimer

An American film and television actor, best known for his portrayal of journalist Edward R. Murrow in the feature fil...

Michael Tucker

Hume Cronyn

as James F. Byrnes

Richard Dysart

as President Harry S. Truman

Hal Holbrook

as Gen. George Marshall

Harold Rowe Holbrook Jr. (February 17, 1925 – January 23, 2021) was an American actor, television director, and write...

Barnard Hughes

as Henry Stimson

John McMartin

as Dr. Arthur Compton

David Ogden Stiers

as Franklin D. Roosevelt

Anne Twomey

as Kitty Oppenheimer

Lawrence Dane

Ron Frazier

as Colonel Pash

Olek Krupa

as Edward Teller

Bernie McInerney

John Pielmeier

as Seth

Ken Pogue

as Dwight D. Eisenhower

Gary Reineke

as Groves's Commanding Officer

Alan Scarfe

John Seitz

as Ralph A. Bard

Tony Shalhoub

as Enrico Fermi

Tony Shalhoub is an American actor. His television work includes the role of Antonio Scarpacci on Wings and Adrian M...

Ester Spitz

as Trude Weiss

Ron White

as Colonel Nichols

Stephan Balint

as Eugen Wigner

Peter Boretski

as Albert Einstein

Patrick Breen

as Richard Feynman

Patrick Breen is an actor and writer.

Vlasta Vrana

George Popovich

as Samuel Goudsmit

Lorne Brass

Michael Sinelnikoff

as Lord Rutherford

Graham Haley

as Haakon Chevalier

Kliment Denchev

as Michael Polanyi

Diana Fajrajsl

as Ilse Polanyi

Timothy Webber

as Colonel Lansdale

Harry Standjofski

as Robert Wilson

Lia Sargent

as Mrs. Wisnovsky

David Gow

as Jack Wisnovsky

Michael Farrell

as Shapp

Isabelle Mejias

as Mrs. Trowbridge

Jonathan Wise

as Robert Serber

George R. Robertson

Dee McCafferty

as William 'Deke' Parsons

Tom Butler

as Captain DeSilva

Tom Butler is a Canadian television and film actor. He best known for his television role on the science fiction ser...

Robert Morelli

as T. O. Jones

Jon Baggaley

as James Tuck

David Bolt

as Harry Gold

David Ferry

Heinar Pillar

as Fleischmann

François Klanfer

as Haagen Kistiakowski

Joel Miller

as George Kistiakowski

Michael J. Reynolds

as Kenneth Bainbridge

Ed McGibbon

as William D. Leahy

Nicholas Kilbertus

as Paul Tibbets

Joe Cazalet

as Air Force Guard

Scott Thomson

Bob Clout

as Alfred MacCormack

Roland Hewgill

as Army General

Stan Gibbons

as John J. McCloy

Terrence Labrosse

as Allan Dulles

Delise Alison

as London Pedestrian

Alex Guard

as British Jr. Officer

Philip Spensley

as British Sr. Officer

Frederick Neumann

as Alexander Sachs

Norris Domingue

as General Pa Watson

Steve Barry

as Los Alamo Scientist (uncredited)

Arthur Holden

as Scientist (uncredited)

Arthur Holden (born August 28, 1959) is a Canadian voice actor. He voices Baba-Miao in Sagwa, the Chinese Siamese Cat...

Romano Orzari

as Leo Szilard's Prime Scientist (uncredited)

Crew of Day One

Discover the backstage crew of Day One →