Glenn Rhee (Steven Yeun) and Maggie Greene (Lauren Cohan) - The Walking Dead - Season 4 Frank Ockenfels 3/AMC/Frank Ockenfels 3/AMC hide caption

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World War Z is just the latest pop-culture incarnation of the Zombie Apocalypse. Adam Frank says the zombies keep coming because they're trying to tell us something. MPC/Paramount Pictures hide caption

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