UPDATE, 5:32 PM: Charlize Theron just got a new movie mother, and it is Christina Hendricks. The Mad Men actress has gone from a supporting role to a lead in the adaptation of Gillian Flynn’s best-selling 2009 thriller Dark Places, I’ve learned. Originally set to play stripper Krissi Cates in the Gilles Paquet-Brenner directed movie, Hendricks now will play Patty Day, the murdered mother of Theron’s Libby Davis character. The producers offered the role to the Emmy-nominated actress after Samantha Morton fell out. Like the book, the film follows Libby learning that the supposed massacre of her family by brother Ben, which she testified in court decades beforehand, might not be what was assumed. Hendrick’s Patty will be seen in a series of flashbacks throughout the movie as the truth of really happened and what Libby really saw becomes clearer. Also starring Chloe MoretzNicholas Hoult and House Of Cards’ Corey Stoll, the pic produced by Exclusive Media, Cuatro Plus Films, Denver & Delilah, Hugo Productions and Mandalay Vision began shooting last week in Louisiana. UPDATE: Former Sopranos star Drea de Matteo has landed the Krissi Cates role. The Emmy Winning de Matteo is repped by the Gersh Agency and Untitled Entertainment.

PREVIOUSLY, AUG. 20: EXCLUSIVE: The movie adaptation of Gillian Flynn’s best-selling thriller about class, rural America, poverty, opportunism and Satanic cults in the 1980s just got one actor larger. Mad Men’s Christina Hendricks has signed on to Dark Places with Charlize TheronChloe Moretz, House Of Cards’ Corey Stoll and Rescue Me’s Andrea Roth. Hendricks will play the older Krissi Cates character in the film from director Gilles Paquet-Brenner. Krissi has been haunted by a secret from her past that could have great implications for Theron’s Libby Day character and her jailed brother Ben (Stoll). In the book, Krissi is a barely-getting-by stripper who had accused Ben decades before of being a child molester and some other very serious misdeeds. Before Dark Places, the multiple-Emmy-nominated Hendricks will be seen in the Ryan Gosling-directed fantasy noir film How To Catch A Monster along with former Doctor Who Matt Smith and Eva Mendes. She’s also in God’s Pocket, a drama directed by her Mad Men co-star John Slattery and starring Phillip Seymour Hoffman, John Turturro. Richard Jenkins and Eddie McGee. Hendricks is repped by ICM Partners and Kritzer Levine Wilkins Griffin Nilon.

Related: ‘Dark Places’ Adds Corey Stoll & Andrea Roth

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