Inspired, says creator Charlie Brooker, by the classic horror film "Dawn of the Dead," this five-episode series chronicles a nightmare scenario in which Britain is taken over by zombies. No one is spared the wrath of the undead ... except the contestants and production staff filming a season of "Big Brother" in the U.K. As they're unaware of what's happening outside, the house becomes a safe haven. Then the doors open on eviction night and all hell breaks loose.