Hercule Poirot's relaxing holiday on the Cornish coast takes an unexpected turn when he meets young and pretty Nick Buckley. For it seems to Poirot that too many accidents have been happening to Nick and Poirot, with the help of Captain Hastings, is determined to prevent another accident becoming a tragedy. But even hiding Nick away in a nursing home does not prevent another attempt on Nick's life, and Poirot has to resort to subterfuge and cunning to solve this tricky case.