When Sarah Fortune, with her impeccable qualifications and chequered history, is sent to a small seaside town in Norfolk, she goes willingly. Sorting out the inheritance problems of the Pardoes, Merton-on-Sea's premier family, promises to distance her from a claustrophobic relationship with Malcolm Cook. Sarah cannot bear to be a captive.
But she soon discovers that guilt, insecurity, unrequited love and a touch of insanity afflict the Pardoes and the town, the legacy of a suicide which took place two years before, when Elizabeth Tysall, a beautiful woman with an uncanny resemblance to Sarah herself, walked into the sea and never came back.
More immediately, Merton chooses to ignore another part of the legacy, the white-haired figure some call a ghost and others call a vagrant who roams the beach and haunts the town, harmlessly. Until he insinuates himself into the power struggles of the Pardoe children and becomes the mysterious and cunning enemy of all concerned.