15. IT

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Stephen King's IT is terrifying because of IT's seemingly endless powers. Tim Curry does an excellent job of being frightening and charismatic as the dangerous Pennywise the Clown, a demented figment of the imagination. The scene where bully Belch is dragged through a sewer pipe is terrifying because you never see IT, you just see IT's dead lights. It had powers of possession and is one of the scariest Steven King adaptations.