You can’t keep a good horror-movie antagonist down. You may defeat the monster and vanquish your fears, but you can’t kill the undead. It always rises again, maybe to terrify someone else instead of you, but it will be waiting and lurking, as sure as light creates shadow.

Maybe that’s the reason so many horror films generate franchises. In the supernatural realm, where ordinary rules of logic and physics don’t apply, the writers can always find some excuse to bring the demon back and make the nightmare a recurring one. Okay, there’s also the fact that sequels are easier to conceive than originals, and that they’re lucrative, but that’s because audiences crave familiarity, even when they’re being shocked and frightened. The sequels keep offering diminished returns, and yet we keep buying the tickets, in the hope that something will scare us the way the first installment did, when we truly didn’t know what was hiding there in the dark.

Check out the list below of some of the most terrifying and enduring horror franchises ever.

Warning: Many of the clips that follow are NSFW.

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