Lots of slogans such as "Be like Dad, Keep Mum" and "Keep it under your Hat" are visible on the walls in various scenes to reinforce the plot of this British wartime movie illustrating how gossipy talk can result in unknowingly giving valuable information to Nazi spies.
as No 23: Mr Davis
as Beppie Leemans
as Maj. Richards
as No 16
as Mr. Barratt
as Brigade Major Harcourt
as Pvt. John
as Lt. Cummins
as Miss Clare
as Mrs. Webster
as Naval captain
as Mr Vemon
as Brigadier Blunt
as Pvt. Durnford
as Intelligence officer
as German General
as ATS drover with puncture
as Colonel
as Neutral Seaman - Irish Joe
as Pvt. Jimmy
as The Frenchman - Captain Mercier
as Careless Talker on Train
as Careless Talker on Train
as Lance-Corporal
as Wing-Cmdr. Kenton
as German Colonel (uncredited)
as Corporal on Train (uncredited)
as Naval Officer (uncredited)
as Builder's Labourer (uncredited)
as Sailor on Train (uncredited)
as Mr. Palmer (uncredited)
as Warden (uncredited)
as Inspector Jolly (uncredited)
as Soldier in Buffet Car (uncredited)
as Ted (uncredited)
as General Cooper (uncredited)