It happens in just about every zombie movie -- a throng of reanimated corpses lumbers toward the farmhouse, shopping mall, pub or army base where the heroes have barricaded themselves. The zombies aren't dead, but they should be. They're relentless and oblivious to pain, and they continue to attack even after losing limbs. Usually, anyone the zombies kill returns as a zombie, so they quickly evolve from a nuisance to a plague
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