Fresh off her first Oscar nomination for her performance in “The Girl With The Dragon Tattoo,” Rooney Mara has found her next project, boarding Steven Soderbergh’s “Side Effects.”

She replaces Blake Lively and joins a cast that now includes Channing Tatum, Jude Law and Catherine Zeta-Jones.

Story revolves around a young woman who is taking large amounts of prescription drugs to deal with anxiety and depression surrounding her husband’s upcoming release from prison.

Open Road will distribute; Lorenzo di Bonaventura, Gregory Jacobs and Scott Z. Burns are producing, with Burns penning the script.

“Side Effects” is the first film Mara has boarded since she finished shooting “Dragon Tattoo” last June.

Sources say Mara had been weighing a handful of offers over the last couple months, including roles in Lionsgate’s “Pride Prejudice and Zombies” and the untitled Kathryn Bigelow-Mark Boal bin Laden project, but she wanted to make sure she picked the right project following “The Girl With the Dragon Tattoo.”

Thesp came close to going with the Bigelow project instead but had to pass on the role that eventually went to Jessica Chastain due to scheduling conflicts surrounding the promotional campaign on “Dragon Tattoo.”

“The Girl With the Dragon Tattoo” has already grossed more than $97 million domestically and should pass the $100 million marker by next weekend.

Mara is repped by WME.