It was no big surprise that "Insidious Chapter 2" won the weekend at the box office, since it's only competition was "The Family," a Robert De Niro mob action-comedy that played to older audiences. But no one expected it to open above $40 million and set a September record.

Given that the new "Insidious" was the follow-up to a low-budget horror film that opened with $13 million, with a relatively obscure cast and director, predictions for the sequel's debut were in the high 20s and low 30s. Instead, the film earned an estimated $41.1 million, making it the largest September opening ever for a live-action movie or a horror movie.

How did "Insidious Chapter 2" manage to outperform expectations by such a huge margin? Here's what it had going for it that pundits may have overlooked.

Director James Wan: He may not be a household name to most moviegoers, but horror fans know him as the director who, with writer/actor Leigh Whannell, created the "Saw" franchise. He also directed this summer's scary sleeper smash "The Conjuring." As far as horror fans are concerned, he's a reliable brand name. (So is Whannell, who wrote or co-wrote both "Insidious" movies.) By the way, Wan has "Fast & Furious 7" coming out next summer, so we'll see how well he does on a non-horror movie with a blockbuster budget.

Franchise good will: In April 2011, "Insidious" opened with $13.3 million, but instead of petering out like most horror movies do, it hung on for weeks, ultimately earning $54.0 million, more than four times its debut. That was just two and a half years ago, so memories of those initial scares are still strong.

"The Conjuring"'s coattails: "Conjuring" has earned a massive $135.4 million, so it's easy to forget that it opened in theaters less than two months ago. So for many horror fans, the last screamfest they truly enjoyed was also a movie directed by James Wan...

Star Patrick Wilson: ... and starring Patrick Wilson. Again, not a huge star, but after "Insidious" and "The Conjuring," he's almost as much a horror brand name as Wan or Whannell.

Continuity: It's not just Wilson who's back from the first "Insidious." So is the rest of the principal cast, including Rose Byrne, Ty Simpkins (as possessed boy Dalton Lambert), Barbara Hershey, Whannell, Angus Sampson, and Andrew Astor. Even Lin Shaye is back as the paranormal investigator killed at the end of the first movie. So fans could feel reassured that "Chapter 2" wouldn't veer too far from the storyline of "Insidious." Indeed the second movie picks up right where the first, with its implied cliffhanger, left off.

Clever marketing: The ads for "Chapter 2" didn't just remind audiences of the scares they got from the first "Insidious" and "The Conjuring." The ads also showed preview audiences screaming.

The PG-13 rating: Unlike "Conjuring," which was rated R, younger teens can get in to see the new "Insidious," giving it a bigger potential audience.

Right place, right time: Initially, the new "Insidious" was to have opened two weeks ago, but it would have faced tough competition with "One Direction: This Is Us" for the young female audience that drives horror movies. (There was also the week-old horror movie "You're Next" in theaters, though that performed poorly and wouldn't have been much of a threat.) Opening this weekend, however, "Insidious" had no horror competition, and the only other wide release was "The Family," a movie appealing primarily to older audiences. Given the likely wide-ranging appeal of next weekend's "Prisoners," it seems "Insidious" got while the gettin' was good.

It's worth noting that none of this has to do with whether "Insidious: Chapter 2" actually delivers on all that buzz. It earned weak reviews (granted, so do most horror movies, but the first "Insidious" did earn better notices) and even just middling word-of-mouth (as indicated by a B+ grade at CinemaScore). Still, that's a better grade than "Insidious" got (a B), and that movie proved to have very long legs. Whether or not viewers feel "Insidious Chapter 2" delivers the chills they expect, they knew what they were in for, and they felt confident that "Chapter 2" would offer more of it.

6- Second Review: Insidious: Chapter 2
Insidious: Chapter 2 Movie Poster
Insidious: Chapter 2
Based on 30 critics

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