By Todd Cunningham
TheWrap

The low-budget, heavy on the scares formula that has made horror films like "The Purge" and "The Conjuring" among the biggest hits of the years continued to reap dividends this weekend as "Insidious: Chapter 2" trounced studio estimates and dominated the box office.

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The FilmDistrict and Blumhouse Productions film opened to north of $41 million in 3,049 locations, according to studio estimates. It had been projected to open in the $30 million range, but built up an impressive head of steam in terms of pre-sales heading into the weekend.

The numbers for the film fall just short of the $41.9 million that director James Wan's previous effort "The Conjuring" opened to last July. The sequel's debut far eclipses the $13.3 million that the original "Insidious" racked up in 2011.

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"Blumhouse has this micro-budget formula down pat and James Wan has mastered the scary movie," Jim Orr, president of distribution at FilmDistrict, said. "This film delivers in every way. The original film built up a lot of good will and this film works seamlessly with the original, but it's even more intense."

With "The Conjuring" and "Insidious: Chapter 2" both breaking out in a big way, Wan has now joined the A-list — a promotion that becomes official when "Fast & the Furious 7" roars into theaters next year with the horror maestro at the steering wheel. See more