Samuel Browne is a tracker in Alaska. When his sister meets a grisly death in San Francisco, he goes there to hunt her killer. As more murders occur, police investigator Buckley Clarke reluctantly joins forces with Sam. The brass are convinced this is a serial killer choosing victims at random, but Sam and Buckley discover a pattern involving health personnel who work in neonatal intensive care. Doctors aren't supposed to play god, but someone's decision years before has driven a killer over the brink. Can they find him?