Haunted houses. Dogs dressed up in Darth Vader costumes. Candy corn-flavored Oreos. Let’s face it: Halloween season is big business.

And nowhere is this more evident than in Hollywood’s box office returns. The latest fright night offering, Annabelle (a story about an overly made-up doll with some serious anger issues) has a domestic total of $80 million so far according to Box Office Mojo—not bad for a movie with an estimated budget of $6.5 million. Your 401(k) should be posting those kinds of returns.

Weird, right? In the real world, none of us would want to get up close and personal with a killer doll or confront a guy who’s wearing a hockey mask and wielding a blood-soaked machete. Yet we’ll shell out twelve bucks to sit in a darkened theater to watch Jason (and Freddie and Michael Meyers) go about their grisly business. What’s up with that?

Here, some theories on why we love that scary feeling:

It makes us feel good

Yep, fear is a natural high—and here’s why: “There’s a strong physiological response when watching horror movies,” says Margee Kerr, PhD, a sociologist at the University of Pittsburgh, who studies fear. As the carnage continues, adrenaline, endorphins, oxytocin, serotonin, and dopamine are being released into your brain and body (Kerr describes it as a “full-on chemical cascade”), creating genuine thrills to go with those chills.

“We experience a kind of arousal from watching horror movies," explains Glenn Sparks, PhD, a professor of communication at Purdue University's Brian Lamb School of Communication. “Your heart rate increases, your skin temperature drops, your blood pressure goes up.” But here’s the thing, says Sparks: It takes time for that feeling of arousal to subside and return to normal baseline level. So even though your frightening experience has ended, that aroused feeling lives on for a while—and makes whatever emotion you're feeling afterward even more intense. “When you think back on a scary movie you saw, you might think, 'Wow—I loved that!' Not really," he says. "What you loved was the aftermath of it.”

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It’s pretty irresistible

Simply put, a lot of us are drawn to the dark side of human nature. Horror films let us experience all sorts of threatening things…but at a distance. Glenn Walters, PhD, associate professor of criminal justice at Kutztown University in Pennsylvania, puts it this way: “We get to explore fear with a safety net.”

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It’s a bonding thing

Fear creates a kind of camaraderie. “When people go through an intense experience together it can bring them closer together,” explains Frank Farley, PhD, a psychologist at Temple University and former president of the American Psychological Association. “In that way, emotions can be contagious—you scream and other people join in. It’s creating a social experience.”

It’s a confidence booster

Believe it or not, being scared can have real psychological benefits. “When people face down fears in safe ways, they feel successful and more confident. You feel as though you’ve not only survived but conquered something threatening,” says Kerr. What’s more, with each nail-biting viewing, you’re actually building a higher tolerance for stress. “In that sense,” says Kerr, “you could think of watching horror movies as training wheels for encountering everyday stress.”

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It’s kind of a turn-on

While it may not sound very PC, fear has a way of causing us to revert back to traditional gender roles, notes Sparks. For example, studies have shown that females tend to find men more attractive when they show ‘mastery’ over their emotions. Guys, on the other hand, find females more attractive—and the viewing experience more enjoyable—when they appear to be vulnerable.

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