Friday 20th January 1961. On the day JFK is sworn in as US President, a storm breaks over Moord Manor, an imposing English country house. Housekeeper Mrs Constance Dribble prepares to receive guests for a weekend party. There’s just one problem: her employer, the enigmatic Mr Di Sorto, has been delayed and won’t be there to greet his guests. So it falls to Mrs Dribble and Runcible — the haughty butler — to do the honours.
As she dusts and polishes, Mrs Dribble talks to the spirits who live in the relics around the house — the suit of armour, a portrait, a stag’s head — and they talk back to her! Runcible hears her talking and demands to know if she has been talking to ghosts again, but she vehemently denies it. He gently admonishes her: “you know what the doctors said!”
Gradually the guests start to arrive: first is alcoholic ex-military man Colonel Muskett, followed by American millionaire playboy Buck Surfett and his bookishly handsome male secretary, Dick Tasion, who, it seems, has a photographic memory. Next to arrive is eminent surgeon Dr Francesca Loosely-Stitcham, swiftly followed by world-famous whodunnit author Mark Myward and his pretty young girlfriend, Minnie Major. Last — making a grand entrance as befits a famous Hollywood starlet — is Regina Lewdley, or ‘Reggie’ to her friends.
The guests are disappointed to learn that their host, Mr Di Sorto, has been delayed, but resolve to make the most of his hospitality in his absence. The guests are formally introduced, and Mrs Dribble notices that one of their number is missing.
In Buck’s bedroom the millionaire dresses for dinner, aided by Dick. They leave, but Dick returns, claiming to have dropped a cuff link. He tells Buck to go on without him. Alone in the room he rummages through Buck’s personal effects, clicking away with his photographic memory.
After dinner they spot an intruder in the grounds. They all run into the garden to apprehend ‘the mystery man’, but the Colonel — being a complete coward — returns to look for a weapon. He thinks he is alone until a mysterious intruder, hidden in the shadows, runs him through with the sword from the suit of armour. When the other guests return from their fruitless search of the garden they discover the dead Colonel with a note pinned to his chest. It accuses him of a dark past and contains a strange word: “our brave Colonel blamed the dead hero to save his own skin. Now you feel his wraak.” Mark arrogantly assumes the role of detective and, in full-on whodunnit mode, surmises that the killer meant to write “wrath”.
Then Reggie spots the mystery man in the grounds again. The men apprehend him and bundle him into the house, a sack over his head. When it’s removed they see a bedraggled man in a black suit, wearing a dog collar. He says he is Audley Pious, the Bishop of Stepney, and Mr Di Sorto’s missing guest. Apparently he missed his train and had to walk from the station through the storm, and got lost in the garden. Buck and Mark accuse him of being the killer — the ‘mystery man’ — but the resourceful Dick finds a copy of ‘Burke’s Peerage’ in the library, which lists all the Bishops in England. A few simple questions prove that the Bishop is indeed who he says he is.
Mrs Dribble calls the police station to report the murder of the Colonel, only to be told that they are stranded — the bridge is down and they are completely cut off. What’s worse, there’s an escaped murderer on the loose!