Mervyn Johns as No 23: Mr Davis

Nova Pilbeam as Beppie Leemans

Reginald Tate as Maj. Richards

John Chandos as No 16

Stephen Murray as Mr. Barratt

Jack Hawkins as Brigade Major Harcourt

Geoffrey Hibbert as Pvt. John

Philip Friend as Lt. Cummins

Phyllis Stanley as Miss Clare

Mary Clare as Mrs. Webster

Basil Sydney as Naval captain

Joss Ambler as Mr Vemon

Brefni O'Rorke as Brigadier Blunt

Alexander Field as Pvt. Durnford

David Hutcheson as Intelligence officer

Torin Thatcher as German General

Thora Hird as ATS drover with puncture

Frederick Leister as Colonel

Charles Victor as Neutral Seaman - Irish Joe

Richard Norris as Pvt. Jimmy

Guy Maas as The Frenchman - Captain Mercier

Basil Radford as Careless Talker on Train

Naunton Wayne as Careless Talker on Train

Johnnie Schofield as Lance-Corporal

Frank Allenby as Wing-Cmdr. Kenton

Victor Beaumont as German Colonel (uncredited)

Mark Daly as Corporal on Train (uncredited)

Ian Fleming as Naval Officer (uncredited)

Hal Gordon as Builder's Labourer (uncredited)

James Knight as Sailor on Train (uncredited)

Charles Rolfe as Mr. Palmer (uncredited)

Jack Sharp as Warden (uncredited)

George Street as Inspector Jolly (uncredited)

Guy Verney as Soldier in Buffet Car (uncredited)

H Victor Weske as Ted (uncredited)

John Williams as General Cooper (uncredited)