Noël Coward as Captain E. V. Kinross R.N. / Captain 'D'

John Mills as Ordinary Seaman Blake / Shorty Blake

Bernard Miles as Chief Petty Officer Hardy / Walter Hardy

Celia Johnson as Mrs. Kinross / Alix

Kay Walsh as Freda Lewis / Freda

Joyce Carey as Mrs. Hardy / Kath

Derek Elphinstone as No. 1

Michael Wilding as Flags

Robert Sansom as Guns

Philip Friend as Torps

Chimmo Branson as Midshipman

Ballard Berkeley as Engineer Commander

Hubert Gregg as Pilot

James Donald as Doc

Michael Whittaker as Sub

Kenneth Carten as Sub-Lieutenant R.N.V.R.

John Varley as Secco

Caven Watson as Brodie

Geoffrey Hibbert as Joey Mackeridge

Richard Attenborough as Young Stoker

Frederick Piper as Edgecombe

Lionel Grose as Reynolds

Leslie Dwyer as Parkinson

Charles Russell as Fisher

John Singer as Moran

Robert Moreton as Coombe

John Boxer as Hollett

Kenneth Evans as Posty

Johnnie Schofield as Coxswain

Franklyn Bennett as Commander Spencer

Charles Compton as № 1. "Tremoyne"

Walter Fitzgerald as Colonel Lumsden

Gerald Case as Jasper

Daniel Massey as Bobby Kinross

Ann Stephens as Lavinia Kinross

Kathleen Harrison as Mrs. Blake

Dora Gregory as Mrs. Lemmon

Penelope Dudley-Ward as Maureen

Barbara Waring as Mrs. Macadoo

Eileen Peel as Mrs. Farrell

Lesley Osmond as Nell Fosdick

Josie Welford as Emily

Kay Young as Barmaid

Trixie Scales as Mona Duke

George Carney as Mr. Blake

Wally Patch as Uncle Fred

Michael Anderson as Albert Fosdick

Jill Stephens as May Blake

Everley Gregg as Nurse

Roddy Hughes as Photographer

Norman Pierce as Mr. Satterthwaite

Juliet Mills as Freda's Baby

Leslie Howard as Narrator (voice) (uncredited)