Natalie Lindstrom has a gift: the power to speak to the dead, to solve crimes by interviewing murder victims. But now Natalie wants to escape, from the voices that fill her head, and from the organisation that has used her as a crime-solving tool - and who now wants to recruit her daughter.

So Natalie takes a job as far from crime and punishment as she can get: with an archaeologist in the mountains of Peru. Her job: to find a trove of priceless artifacts - by channelling those who lived and died at an ancient Incan site. But in the towering Andes, Natalie enters a 500-year-old storm of betrayal, murder, greed, and rage - and she cannot silence the voices of the dead.

The slaughtered reach out to her. The slaughterers boast of their crimes. Alone, cut off from her family, Natalie faces a chilling realisation: every truth she uncovers is leading her one step closer to a terror beyond imagining.

In a world where the dead can testify against the living, someone is getting away with murder. To every generation a select few souls are born with violet-coloured eyes - and the ability to channel the dead. Both rare and precious, and rigidly controlled by a society that craves their services, these Violets perform a number of different social duties. But now the Violets themselves have become the target of a brutal serial murderer - a murderer who has learned how to mask his or her identity even from the victims. Can FBI agent Dan Atwater, aided by Violet Natalie Lindstrom, uncover the criminal in time? Or will more of Natalie's race be dispatched to the realm that has haunted them all since childhood?