The seven dials mystery : As a practical joke, houseguests at the country estate of Sir Oswald Coote put eight alarm clocks under Gerry Wade's bed, only to find a missing clock and a dead man.

Crooked house : Criminologist Charles Hayward becomes a special assistant to Scotland Yard when his fiancée's grandfather is murdered, and her entire family comes under suspicion.

Ordeal by innocence : Mrs Argyle, benevolent and tyrannical adoptive mother to five children, is struck down in her study with a poker. The verdict is murder. And while serving a life sentence for killing his mother, Jacko Argyle dies. Two years later a stranger shatters the peace of the Argyle household. Can Arthur Calgary provide the missing link in Jacko's defence? Was Jacko sentenced for a murder he didn't commit? Calgary's new light on the crime is not received by the Argyle family as joyfully as he expected, for if Jacko didn't murder his mother, who did?