Shortly after her second marriage, the former Mrs Underhay finds herself widowed and in possession of her late husband's considerable fortune, a fortune on which several members of his family were counting.
This is a post-war novel, and there are signs in it that the world of safety and comfort is gone forever. Several mentions are made of increasing prices, higher taxation and the like, and the fact that the war has changed everyone, not always for the better.
This is not one of Ms Christie's lighter reads: the book is full of well-drawn characters with complex identities and motivations. It shows that people, no matter how good they may seem, can have conflicting emotions, and that, under the right circumstances, almost anyone can commit the most terrible crimes.