This is a movie about fearing the end of the world. It’s more about anxiety than the apocalypse. Whatever metaphors are contained in the script, the sense of impending doom is palpable, and unsettling. The whole film plays like a bad dream, where hidden meaning is secondary to throat-sucking dread. All horror films are about the same thing, but they let you off when the nightmare takes shape. In Take Shelter, fear is amorphous. We don’t know if the worst is real, or inside a man’s head. And that uncertainty is the conceit. Worry drives you mad. But worry warns you of danger too. It paralyses you even as it prompts you to act. That’s why the gift of prophesy is so alluring. Once you’re certain, you don’t feel angst.