Other Mommy looks to be firmly in charge of the weekend box office as The Social Reckoning seeks to find more engagement.

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Jessica Chastain leads Universal Pictures’ Other Mommy, which collected $3.6 million from Thursday previews. Director Rob Savage‘s horror title opens in 3,200 North American theaters, with the studio projecting a $20 million opening for the movie about a sinister entity showing up in a young girl’s closet.

Carrying a $19 million production budget, Other Mommy will not have the benefit of critical support, as the movie holds a rough 18 percent approval rating from reviewers on Rotten Tomatoes. In his review for The Hollywood Reporter, critic Richard Lawson wrote that the movie is “an attractive but mostly vacuous collection of jumpy bits and half-baked mythology.”

Also debuting this weekend is Sony Pictures’ The Social Reckoning, which grossed $650,000 from Thursday previews. The $30 million-budgeted film opens in 2,600 North American theaters, with the studio expecting around $7 million for the frame. By comparison, last week’s Tom Cruise-led Digger pulled in $1.2 million in previews on its way to just $8 million for the weekend, although that Warner Bros. title holds a much heftier budget.

Aaron Sorkin helmed the fact-based follow-up to 2010’s The Social Network, director David Fincher’s beloved feature about the founding of Facebook that earned Sorkin an Academy Award for his screenplay. Jesse Eisenberg, who landed an Oscar nomination for his portrayal of Mark Zuckerberg in The Social Network, did not return for the new movie, with Jeremy Strong taking over the part. The Social Network opened at No. 1 with $22.4 million before reaching a global cume of $224 million.

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Mikey Madison and Jeremy Allen White also star in the thriller about a Facebook staffer (Madison) working with a journalist (White) to expose concerning truths about the company. Critics have been mixed, with The Social Reckoning holding a 57 percent Rotten Tomatoes score, although THR chief film critic David Rooney’s review heralded it as an “engrossing whistleblower thriller.”

During a recent conversation with THR, Sorkin left the door open for a third Facebook-centric film. “Whenever I’m done with something, I’m always like Sisyphus at the bottom of the mountain again,” the filmmaker explained. “This movie opens Oct. 9. On Oct. 10, I’m going to be at the bottom of the mountain, and I will have no idea. So if a good story comes along and it takes place at Facebook, sure.”

Also hitting select theaters this weekend are Alex Gibney’s documentary Musk, Chris Rock’s Misty Green and biographical drama Tenzing.

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