A murderer is on the loose on the streets of New York City: nicknamed the Doomsday Killer, he's claimed six victims in just two weeks, and the city is terrified. Even worse, the police are mystified: the victims have nothing in common, defying all profiling, and all that connects them is that each received a sick postcard in the mail before they died - a postcard that announced their date of death. In desperation, the FBI assigns the case to maverick agent Will Piper, once the most accomplished serial killing expert in the bureau's history, now on a dissolute spiral to retirement.