Families can be monstrous and their secrets dangerous, as New Scotland Yard detectives Thomas Lynley and Barbara Havers have discovered. The pair are puzzled that the Hampstead police need their help investigating the vehicular murder of a middle-aged divorcée, until they find evidence that one of their own superiors once knew the dead lady very well indeed.

Twenty-eight year old virtuoso violinist  Gideon Davies has lost not only his memory of music but also his ability to play the instrument he mastered as a five-year-old prodigy. One fateful night at Wigmore Hall, he lifted his violin to play in a Beethoven trio, and everything in his mind related to music was gone.

Gideon suffers from a form of amnesia,the cure for which is an examination of what he can remember. And what he can remember is little enough until his mind is triggered by the weeping of a  woman and a single name: Sonia. One rainy evening, a woman called

Eugenie travels to London for a mysterious appointment. But before she is able to reach her destination, a car swoops out of nowhere and kills her in the street.

  In pursuing the killer of Eugenie, Thomas Lynley, Barbara Havers and Winston Nkata come to know a group of people whose lives are inextricably connected by a long-ago death, a trial,and a prison sentence handed down as  retribution for a crime no one has spoken of for twenty years.