Hercule Poirot attends the grand opening of the El Ranchero restaurant at the invitation of one of its new owners, none other than Capt. Hastings. He collapses however and is rushed to hospital only to be told that for a man his age, he needs to lose weight or risk a worsening heart condition. The doctor and Miss Lemon soon book him into the Sandy Cove hotel, a health spa, for two weeks with Hastings going along to keep him company. The hotel hosts the usual assortment of guests but also includes a well known actress, Arlena Stuart. She is disliked by many at the hotel including her husband and stepson, whom she treats badly; Christine Redfern whose husband Patrick is carrying on a flirtation, if not more, with her; and a fanatical Minister who sees her as the embodiment of sin. As a result, Poirot has no shortage of suspects when she is found strangled on the beach. He does however have a very difficult knot to untangle.
—garykmcd