Seattle police detective Lou Boldt and police psychologist Daphne Matthews return in No Witnesses to confront the most challenging case of their careers. People are dying throughout Seattle - victims of a madman who is placing poisoned food in neighborhood supermarkets. But the criminal is intelligent: he writes the police chilling extortion letters - faxed directly from a laptop computer over public telephone lines - and retrieves his ransom electronically, through automatic teller machines in hundreds of locations around the city. And while he is a murderer, his crimes take place miles and often days away from his innocent victims' demise.