He hides in the abandoned subway tunnels under New York City. An ex-Marine who was left to die in the steaming jungles of Vietnam back in 1975.
Forty years later, he's back.
Homicide Detectives Iris Williams and Annette Toni had thought they'd seen it all until they are called in to investigate the murder of an entire family. As the elusive serial killer remains hidden, the city spills over into a panic. Will Detectives Williams and Toni combine skills be enough to catch a living nightmare? Or will the detectives lose themselves in the frightening world of a man the media is calling: THE PIGGYBACK KILLER.