William Wiles is an easygoing thirty-something, a bartender who lives a quiet life alone until a serial killer singles him out - not to kill him, but to force him to decide who the next victim will be Billy finds the first note 'If you don't take this note to the police and get them involved, I will kill a lovely blonde schoolteacher If you do take this note to the police, I will instead kill an elderly woman active in charity work You have four hours to decide The choice is yours' Billy pays an informal visit to an acquaintance, Lanny Olson, who is a policeman, and who thinks the note is a prank The schoolteacher dies With more communications from the killer, Billy is drawn deeper into an accelerating nightmare