It is 1968, and Dr. Robert Morgan lives in a world where everyone else has been infected by a plague that has turned them into undead, vampiric creatures that cannot stand sunlight, fear mirrors, and are repelled by garlic. They would kill Morgan if they could, but they are weak and unintelligent. Every day Morgan carries out the same routine: he wakes up, marks another day on the calendar, gathers his weapons, and then goes hunting for vampires, killing as many as he can and then burning the bodies to prevent them from coming back. At night, he locks himself inside his house. A flashback sequence explains that, three years earlier, Morgan's wife Virginia and daughter Kathy had succumbed to the plague before it was widely known by the public that the dead would return to life. Instead of taking his wife to the same public burn pit used to dispose of his daughter's corpse, Morgan buried her without the knowledge of the authorities. When his wife returned to his home and attacked him, Morgan became aware of the need to kill the plague victims with a wooden stake. Morgan hypothesizes that he is immune to the bacteria from a bite by an infected vampire bat when he was stationed in Panama, which may have introduced a diluted form of the plague into his blood. One day, a dog appears in the neighborhood. Desperate for companionship, Morgan chases after the dog but does not catch it. Sometime later the dog appears, wounded, at Morgan's doorstep. He takes the dog into his home and treats its wounds, looking forward to having company for the first time in three years. He quickly discovers, however, that it, too, has become infected with the plague. Morgan is seen burying the dog, which he has impaled with a wooden stake. Morgan sinks further into depression and loneliness. After burying the dog, Morgan spots a woman in the distance. The woman, Ruth, is terrified of Morgan at first sight and runs from him. Morgan convinces her to return to his home, but he is suspicious of