Mr Scobie's arrival at the nursing home of St Christopher and St Jude - and into the clutches of Matron Hyacinth Price - is accidental. Self-educated and still preserving the gift of idyllic memory and wish, Mr Scobie stands apart from the others. For long-term resident and eccentric, Miss Hailey, he represents a kindred spirit; for Matron Price - a lady of questionable practices - the latest victim... But unwittingly Mr Scobie has some recourse - his very simple riddle. Its answer, an ancient commonplace, jolts Matron Price. Yet it is Mr Scobie's nephew, Hartley, and the group of nocturnal poker players, who ultimately change Matron Price's establishment.