Mrs Bradley visits the seaside resort of Porth Carrack, where she is to present Inspector Christmas with the freedom of the town. The vicar's daughter is found dead, strangled with a worsted viper.

Mrs Bradley tries to solve the mysterious murder of her friend's relative who is found poisoned in her garden, while chauffeur George confronts some skeletons in his closet.

When a travelling circus stops at a village, the knife thrower's partner is stabbed to death, prompting an investigation by Mrs Bradley.

Mrs Bradley is asked to give a lecture at her old school and gets involved in murder, illegimate children, lesbianism, spiders and the Mikado.

When Mrs Bradley arrives at her god-daughter's engagement party, nobody expects the night to end in murder. Aided by her chauffeur George, Mrs Bradley sets out to discover the truth.