A group of people in an old dark house are terrorized by a mysterious hooded figure dressed in black who proceeds to kill them off one by one.
When a celebrated financier commits suicide, the police begin to suspect that the dastardly and elusive "Shadow" was blackmailing him, and will continue to extort from the rich and famous until he is apprehended. Meantime, some petty thieves decide to target the country home of the Commissioner of the Metropolitan Police (Felix Aylmer). When an inspector discovers a vital clue that he takes to his boss who locks it securely in his safe, our two stories combine and his house guests begin to fear for their very lives... The story is a bit convoluted, but the performances from Henry Kendall (the rather gaffe-prone "Reggie") and Cyril Raymond keep the suspense mounting, albeit very, very gently, as the net slowly tightens on the hooded spectre. It's fun, this - a simple, occasionally quite funny mystery that flows well and is enjoyable for just over an hour.