Cliff Robertson

Lt. John F, Kennedy

Ty Hardin

Ensign Leonard J. Thom

James Gregory

Commander C.R. Ritchie

Robert Culp

Ensign George 'Barney' Ross

Grant Williams

Lt. Alvin Cluster

Lew Gallo

Yeoman Rogers

Errol John

Benjamin Kevu

Michael Pate

Lt. Reginald Evans

Robert Blake

Charles 'Bucky' Harris

Biff Elliot

Edgar E. Mauer

Norman Fell

Edmund Drewitch

James McCallion

Pat McMahon

Joseph Gallison

Harold Mamey

Sam Gilman

Raymond Starkey

Buzz Martin

Maurice Kowal

John Ward

John Maguire

George Takei

Helmsman on Japanese Destroyer (uncredited)

Andrew Duggan

Narrator (uncredited)

Roger Davis

Radioman (uncredited)

George Gaynes

PT Flotilla Captain (uncredited)

Chuck Hicks

Cook (uncredited)

Dale Ishimoto

Commander (uncredited)

Sheb Wooley

Edmund Drewitch's Scream (archive sound) (uncredited)