The Seven Dials Mystery

At Chimneys, a great English country house leased from Lord Caterham to steel magnate Sir Oswald Coote, a house-party of Bright Young Things plans a prank on Gerry Wade, a habitual late riser: they hide eight alarm clocks in his bedroom, set to ring at staggered intervals. Gerry never wakes. He is found dead of chloral poisoning, and someone has ranged seven of the clocks in a neat row along his mantelpiece and hurled the eighth out of the window. Bundle Brent, Lord Caterham's fearless daughter, returns home and finds an unfinished letter Gerry was writing to his half-sister Loraine, warning her off "that Seven Dials business." Driving to London in her Hispano-Suiza, Bundle nearly runs down a young man staggering from a hedgerow; his dying words are "Seven Dials — tell Jimmy Thesiger." The man is Ronny Devereux, Gerry's friend — shot from cover with a rifle, not struck by her car.

Bundle allies with Jimmy Thesiger and Loraine, and separately with Superintendent Battle of Scotland Yard. She discovers a masked secret society meeting in a soundproof cellar behind the Seven Dials Club, chaired by an absent "No. 7," and overhears them plotting to steal a revolutionary steel-hardening formula being handed to the British Air Minister at George Lomax's Wyvern Abbey house-party. On the night of the theft the papers are stolen, then recovered on the terrace by Loraine — after Jimmy is shot fighting a supposed climber. Bundle recognises the beautiful Countess Radzky, by a small mole below her shoulder blade, as the "No. 1" from the cellar. Battle then reveals the ultimate twist: the Seven Dials is not a criminal gang but a secret-service band of amateurs founded by Gerry Wade — with Bill Eversleigh, a Russian anti-Bolshevist, a Hungarian count, an American journalist, and Ronny's actress fiancée among its members, and Battle himself as No. 7. The real killer of Gerry and Ronny is Jimmy Thesiger, aided by Loraine — who is not Gerry's sister but Jimmy's fellow-conspirator. Bill baits Jimmy into a trap; both are arrested. Bundle agrees to marry Bill.