Actress Mackenzie Davis is in negotiations to play the lead opposite Kristen Stewart in the upcoming romantic comedy "Happiest Season". Davis starred as the night nanny and title character in last year's "Tully" opposite Charlize Theron. She was one of the leads in the series "Halt and Catch Fire" and appeared in "The Martian" and "Blade Runner 2049". 

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The studio bought worldwide rights to the holiday-themed "Happiest Season" from the writing team of Clea DuVall and Mary Holland. DuVall, who directed the 2016 indie "The Intervention", is also on board to controls what will be her directorial debut on a major studio feature

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"Happiest Season" focus around a young woman whose plan to propose to her girlfriend while at her family's annual holiday party is turn overfed when she find her partner has not yet come out of her traditional parents' shadow. Sony had no comment on Davis's casting. She's playing a role  as a soldier-assassin in Tim Miller's upcoming "Terminator" reboot, joining Linda Hamilton and Arnold Schwarzenegger.