A woman is shot dead while looking for her dog in a woodlot below her house. But local vet, Dr. Erica Merrill, who heard the shot, and her boyfriend Clay Caldwell, a deputy sheriff, don't think the killing was an accident, but that the wrong person was accidentally shot. When another attempt at murder is made, the police have two crimes with no suspects, and with no idea who was supposed to be murdered. The killer is furious at having shot the wrong person, the first episode in a grisly game of cat and mouse, where one player tries to trap the other, who succeeds in evading the deadly traps until the final resolution, which Erica tries to prevent.