About the title
For two years now David has been living in isolation in a house in the woods. Every day he sends a package of his blood to his wife Sam, who works in a lab trying to synthesize a cure for the dangerous virus ravaging the planet - a virus to which he turns out to be immune. His only connection to the outside world is a drone that collects his blood and delivers food, and rare video calls with his wife. Going mad from loneliness, David starts dialing every number in the phone book at random and soon reaches another survivor.