Don Knotts
Henry Limpet
Acting
Carole Cook
Bessie Limpet
Acting
Jack Weston
George Stickel
Acting
Andrew Duggan
Harlock
Acting
Larry Keating
Admiral P.P. Spewter
Acting
Oscar Beregi Jr.
Nazi Admiral (as Oscar Beregi)
Acting
Charles Meredith
Fleet Admiral
Acting
Elizabeth MacRae
Ladyfish (voice)
Acting
Paul Frees
Crusty (voice)
Acting
Wesley Gale
Man Staring Into Window (uncredited)
Acting
Leon Alton
Officer at Fleet Admiral's Meeting (uncredited)
Acting
Phil Arnold
Short Fisherman (uncredited)
Acting
George Bruggeman
Nazi Officer (uncredited)
Acting
Paul Busch
Sonar Man (uncredited)
Acting
Al Checco
Sailor (uncredited)
Acting
Cordy Clark
Giggling Girl (uncredited)
Acting
Roydon Clark
Sailor (uncredited)
Crew
Sayre Dearing
Passerby/Naval Officer at Meeting (uncredited)
Acting
George DeNormand
Nazi Officer (uncredited)
Acting
Dan Dowling
Naval Officer at Meeting (uncredited)
Acting
Harold Dyrenforth
U-Boat Captain (uncredited)
Acting
Louie Elias
Sailor (uncredited)
Acting
Lisabeth Field
Miss Barnes (uncredited)
Acting
Logan Field
Lieutenant (uncredited)
Acting
Fred Fisher
Officer at Fleet Admiral's Meeting (uncredited)
Acting
Walter Friedel
Nazi Officer (uncredited)
Acting
George Golden
Naval Officer at Fleet Admiral Meeting (uncredited)
Acting
Marv Goux
Nazi Officer (uncredited)
Acting
John Hale
Sailor (uncredited)
Acting
Sam Harris
Officer at Fleet Admiral's Briefing (uncredited)
Acting
George Holmes
Scientist (uncredited)
Acting
Joseph La Cava
Officer at Fleet Admiral's Briefing (uncredited)
Acting
Mike Lally
Naval Officer at Meeting (uncredited)
Acting
Harold Miller
Officer at Fleet Admiral's Briefing (uncredited)
Acting
Charles Morton
Boat Captain (uncredited)
Acting
Henry Norell
Sailor (uncredited)
Acting
Jack Pepper
Sport Fishmern (uncredited)
Acting
Montie Plyler
Helmsman (uncredited)
Acting
Felix Reinsch
Submarine Captain (uncredited)
Acting
Waclaw Rekwart
Passerby (uncredited)
Acting
Heinz Sadler
Sonar Man (uncredited)
Acting
Scott Seaton
Old Man in Shipping Office (uncredited)
Acting
Jack Shea
Sailor (uncredited)
Acting
John Truax
Policeman (uncredited)
Acting
Edward Wermel
Scientist (uncredited)
Acting
Feridun Çölgeçen
Scientist (uncredited)
Acting
Peter Adams
Lieutenant (uncredited)
Acting