Horror blockbuster ‘It’ completely crushed box-office expectations. What happened?

New Line Cinema’s blockbuster horror movie “It,� adapted from the Stephen King novel, is expected to dominate the box office for a second straight weekend after a record-breaking debut, further demonstrating the power of the horror genre to draw audiences.

This weekend, analysts expect “It� to collect $55 million domestically, easily retaining the No. 1 position and holding off two new wide releases: Lionsgate’s and CBS Films’ “American Assassin,� and Paramount Pictures’ “mother.� That would be a 55% week-to-week drop for “It,� a solid hold for a big horror film.

That would continue an extraordinary run for the Andy Muschietti-directed film about seven Maine kids terrorized by a killer clown. The movie took in a whopping $123 million in ticket sales in the U.S. and Canada through Sunday, doubling early industry expectations and crushing records for the biggest September opening and the largest launch for a horror film. It also provided some welcome relief to the industry’s box office doldrums.

Although it’s hardly a shock that “It� did well commercially, given the popularity of the source material, the size of its debut took industry analysts by surprise. But a unique confluence of factors helps explain the film’s massive box office win.

What’s floating ‘It?’

For one thing, “It� benefited from fortuitous timing.

In the last few weeks, there simply hasn’t been enough other compelling studio content to bring people to the theaters. The dearth of other popular movies helped turn “It,� backed by a powerful marketing campaign from Warner Bros. and bolstered by generally positive reviews, into a must-see event, said Paul Dergarabedian, senior media analyst at ComScore.

“The fact that things were so slow for so long made people even more excited,� he said.

“It� also had the nostalgia factor in its favor, appealing to moviegoers who had read the book as kids or seen the Tim Curry portrayal of Pennywise the Clown in the 1990 television miniseries.

Lastly, horror in general has proved a reliable genre for drawing people to cinemas, even as other non-superhero movies struggle to get attention. Horror benefits from the communal experience of seeing a movie in a dark theater, a factor that has boosted this year’s cluster of hits, including “Split,� “Get Out� and “Annabelle: Creation.�

“People love being scared together in a theater, and I'm sure there was a lot of repeat viewing so people could get that again,� Dergarabedian said.

If “It� does as well as projected in its second weekend, analysts expect the movie to eventually gross more than $300 million in the U.S. and Canada. It’s also doing well overseas, taking in $66.3 million internationally as of Sunday from countries including Britain, Russia and Australia.

‘Assassin’ vs. ‘mother’

As “It� rules the multiplex, two mid-budget movies opening this weekend should also generate strong box office sales, grossing $10 million to $15 million each.

Lionsgate and CBS Films will try to draw action fans to theaters with “American Assassin,� about a man who becomes a special operative after his girlfriend is killed in a terrorist attack. Dylan O’Brien (“The Maze Runner�) stars, along with Michael Keaton as a the Cold War veteran who takes the new recruit under his wing.

The studios are hoping the movie performs as well as action films such as “John Wick� (2014) and “The Mechanic� (2011), which opened to $14 million and $11 million, respectively, and both spawned sequels by courting a mostly male audience.

“Mother,� a twisted psychological thriller starring Jennifer Lawrence and Javier Bardem, is the latest film from edgy director Darren Aronofsky, known for acclaimed films such as “Black Swan� and “The Wrestler,� and his controversial big-budget biblical epic “Noah.� “Mother,� which has already proved to be divisive among critics at the Venice and Toronto film festivals, follows a couple whose tranquil lives are thrown into chaos when unexpected visitors come into their stately, secluded home.

Both films’ debuts could take some box office damage from the continued popularity of “It,� which will probably draw some of the male action fans targeted by “American Assassin,� as well as horror aficionados interested in “mother.�

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