Humankind has been wiped out by a zombie invasion which proceeded to move down the food chain, infecting every species of plant and creature on earth. Due to the denial of having to face a banal and meaningless existence, the human zombies rallied together creating order via a new government. Soon after, everything ran as it had before the invasion and no one remembered or accepted that they were dead.
Samuel Glebe is the only zombie left who remembers the truth, and has been diagnosed with Coltard's Syndrome due to his claims. Sam is uncertain if the authorities are covering up the invasion or if he really does suffer from delusions, and must decide whether to undergo electro-convulsive therapy and risk forgetting what could be the truth, or believe in himself and persuade the world to accept what has happened at the risk of living forever in sorrow.