A genetically modified virus mutates, transforming everyone it infects into zombies, wiping out most of the human race. Across the world, small pockets of survivors fight to stay alive and escape the terrifying hordes of flesh eaters. Tom, Becky and their two children are trying to fight their way to safety, and finding other survivors along the route, their numbers swell. Their ultimate goal is to make their way to the place they've come to call their Zombie Castle, a place they hope is defensible, where they can survive and prosper, safe from the attacking zombies. It represents to them an ancient symbol of power and strength, the two elements crucial to their continued survival. Knowing there is safety in numbers, the group works together, their hope being that they can find more family and friends still alive to take with them. They begin the daunting journey to find it.