Rosamund Pike Emerges as Front-Runner to Star in David Fincher's 'Gone Girl' (Exclusive)

"Gone Girl" by Gillian Flynn

The director is seeking the "Jack Reacher" actress to play the female lead opposite Ben Affleck in the hit novel adaptation, which will be co-financed 50-50 by 20th Century Fox and New Regency.

This story first appeared in the July 26 issue of The Hollywood Reporter magazine.

Ben Affleck has taken the mystery out of who will star in David Fincher's twisty whodunit Gone Girl. But apropos of the subject matter, Gone Girl still has a few riddles to unfurl before its planned September shoot.

Affleck (WME, Ziffren Brittenham), fresh from his best picture Oscar for directing and producing Argo, has signed on to star as a philandering husband whose wife goes missing on the morning of their five-year anniversary. Based on Gillian Flynn's runaway best-seller that sold 1.9 million copies in 2012 (second only to the Fifty Shades of Grey trilogy), the film will be co-financed 50-50 by 20th Century Fox and New Regency, according to sources. The Regency move reunites Fincher with Regency CEO Brad Weston, with whom he has a close relationship. (During his days at Paramount, Weston championed Fincher's The Curious Case of Benjamin Button and Zodiac.)

But still remaining to be cast is the titular missing wife, which would be a juicy and high-profile role for a thirty-something actress. A project insider dismisses the possibility of Charlize Theron taking on the project, as had been reported. "Charlize is not doing this movie," emphasizes the source. A studio insider also rules out Natalie Portman -- who had been in the mix to star in Fincher's The Girl With the Dragon Tattoo before he cast Rooney Mara -- and Emily Blunt as potential candidates due to their availability. Reese Witherspoon, who optioned the book last summer via her Type A production company, is on board as a producer only and will not star.

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"There's no shortage of women interested, [and it] will just come down to who Fincher wants," the studio source notes. Jack Reacher co-star Rosamund Pike, whose name has never been mentioned in conjunction with Gone Girl, is said to be the latest contender.

Also a question mark is the shape of the screenplay, which is considered to be a particularly tricky adaptation given that much of the first half of the book is told through diary entries. Flynn is adapting, though the author has not penned a screenplay before. But the project insider says at this point there is no need for an expensive 11th-hour rewrite. "Gillian is taking it all the way with David," the insider insists. "They've found a great rhythm together."

With Flynn's script nearly ready to shoot, Affleck has agreed to push back Live by Night, a film based on a Dennis Lehane novel that he will direct and star in for Warner Bros.

Still, one possible sticking point is Gone Girl's budget, which is in the process of being finalized. Budget issues torpedoed Fincher's chances of directing a 20,000 Leagues Under the Sea remake for Disney. Fincher's chances of helming a sequel to Dragon Tattoo, which Sony shot on a $90 million budget, are all but dead. But the studio source says Gone Girl is expected to stay within the stratosphere, noting that "it's not free rein" for Fincher.

Twitter: @TatianaSiegel27