This was one of a number of "war" films made in the late thirties before the outbreak of war.This was made shortly after the signing of the Munich agreement.It reflects the fears of the audience.It is implied that the enemy will be Germany.One of the characters says Ach so.Geoffrey Toone is a naval officer charged with the job of stopping the plans of the enemy to invade England across the North Sea.His girlfriend lives in a house which is a hotbed of spies and fifth columnists.The idea of fifth columnists was a significant feature of the early war years.By the way the cook is played by Joan Fred Romney not the immortal Fred.
