Paul Graves knows evil to the bone. He confronted it first as a boy, when he witnessed the torture and murder of his sister. Now he writes mystery stories set in gaslight New York, a world coloured by Graves' own past. Graves is invited to spend the summer at Riverwood, at artists' community in upstate New York. But for all its splendour and isolation Riverwood was once touched by crime - a teenage girl from the estate was murdered fifty years before. When Graves is asked to investigate the murder it is more than just the exploration of a long-past crime: he must apply the art of mystery fiction to the murder, then write a story that will enable the victim's mother finally to find peace.