Jack Hawkins

Ericson

Donald Sinden

Lockhart

Denholm Elliott

Morell

John Stratton

Ferraby

Stanley Baker

Bennett

Liam Redmond

Watts

Meredith Edwards

Yeoman Wells

Bruce Seton

Tallow

John Warner

Baker

Barry Letts

Raikes

Gerard Heinz

Polish Captain

Fred Griffiths

Gracey

Glyn Houston

Phillips

Virginia McKenna

Julie Hallam

Megs Jenkins

Tallow's Sister

June Thorburn

Doris Ferraby

Moira Lister

Elaine Morell

Alec McCowen

Tonbridge

Laurence Hardy

Sellars

Sam Kydd

Carslake

John Singer

Gray

Andrew Cruickshank

Scott Brown

Harold Goodwin

ASDIC Operator

George Curzon

Admiral at Party

Don Sharp

Lieutenant-Commander

Russell Waters

A.R.P. Warden

Walter Fitzgerald

Warden (uncredited)

Paddy Joyce

Sonar Operator (uncredited)

Richard Leech

Sailor (uncredited)

Jim Brady

Sailor in Water

Alan Webb

Admiral Murray-Forbes (uncredited)