John Mills
Role: Cpl Tubby Binns
Richard Attenborough
Role: John Holden
Bernard Lee
Role: Charles Foreman
Robert Urquhart
Role: Mike
Ronald Hines
Role: Private Miles
Sean Barrett
Role: Frankie
Roland Curram
Role: Harper
Meredith Edwards
Role: Dave Bellman
Michael Bates
Role: Froome
Michael Shillo
Role: Jouvet
Eddie Byrne
Role: Commander (Tough's Yard)
Lionel Jeffries
Role: Colonel (Medical Officer)
Victor Maddern
Role: Merchant Seaman
Anthony Nicholls
Role: Military Spokesman
Bud Flanagan
Role: Himself
Chesney Allen
Role: Himself
Kenneth Cope
Role: Lieutenant Lumpkin
Warwick Ashton
Role: Battery Sergeant Major
Peter Halliday
Role: Battery Major
John Welsh
Role: Staff Colonel
Lloyd Lamble
Role: Staff Colonel
Cyril Raymond
Role: General The Viscount Gort V.C.
Nicholas Hannen
Role: Vice Admiral Ramsay
Patricia Plunkett
Role: Grace
Michael Gwynn
Role: Commander (Sheerness)
Fred Griffiths
Role: Old Sweat
Christopher Rhodes
Role: Sergeant on the beaches
Harry Landis
Role: Dr. Levy
Patrick Allen
Role: Sergeant on Parade Ground
Liz Fraser
Role: Worker in Holden's Factory (uncredited)
Michael Brennan
Role: Paddle Steamer Captain (uncredited)
Bernard Cribbins
Role: Thirsty Sailor (uncredited)
John G. Heller
Role: German Soldier (uncredited)
John Phillips
Role: Boat Owner Spokesman (uncredited)
William Squire
Role: Captain (uncredited)
Tim Turner
Role: Officer (line of men in sea) (uncredited)
Howard Lang
Role: Chief - Sheerness Dockyard (uncredited)