Isobelle Swanson is making her usual train journey into London one crisp morning, when she meets Evelyn Hertford, a specialist architect as beautifully striking as the converted water tower in which she lives. This is a story about two women who fall very much in love and how they deal with their relationship and the impending wedding of Isobelle's sister, Fiona. A forthright Evelyn tells of her tortured past, for she is the subject of a vitriolic stalker whose malignant presence haunts the two young women through the course of the book. With the increasingly threatening behaviour of the stalker juxtaposed with the fevered imminence of the wedding, the conclusion aims to hold the reader spellbound to the end.