As a deadly battle rages over Jigsaw's brutal legacy, a group of Jigsaw survivors gathers to seek the support of self-help guru and fellow survivor Bobby Dagen, a man whose own dark secrets unleash a new wave of terror.

The world is full of zombies and the survivors have barricaded themselves inside a walled city to keep out the living dead. As the wealthy hide out in skyscrapers and chaos rules the streets, the rest of the survivors must find a way to stop the evolving zombies from breaking into the city.