The living dead have overtaken humanity. The last remnants of the human race live inside a walled city as they come to grips with the situation. The wealthy live in sealed skyscrapers as the poor fend for themselves on the streets. Protecting them is an enormous tank called Dead Reckoning, controlled by a group of people led by Riley. But when Riley loses command of the tank to an insane man bent on destroying the city, he must save it from Dead Reckoning as those who walk beyond the walls of the city slowly develop new abilites and become a much greater threat to humankind.