Rooney Mara will replace Carey Mulligan in Spike Jonze's latest film.
The 'Girl With The Dragon Tattoo' actress is set to take a role in the untitled drama, which Carey dropped out of citing "scheduling conflicts", and although details have been kept a secret it will feature a man who falls in love with the voice of a computer.
It is also thought to include scientists gathering to discuss catastrophic events.
Joaquin Phoenix, Amy Adams and Samantha Morton will all star in the project although it is unclear which parts everyone will play.
Megan Ellison is producing through Annapurna Pictures in the movie which Spike also wrote. He has not directed a movie since 2009's 'Where The Wild Things Are'.
Rooney will play the leading role of Emily Hawkins in the movie about a woman with a prescription drug addiction whose problems increase when she is forced to come to terms with her husband being released from prison after three years, and she begins an affair with her doctor.
Jude Law, Channing Tatum and Catherine Zeta-Jones will also star in the movie, which has been written by Scott Z. Burns.
In January, it was announced that Rooney had replaced Blake Lively in Steven Soderbergh's 'Side Effects' in her first major signing since appearing alongside Daniel Craig in the English language version of 'Girl with the Dragon Tattoo'.
The hard-edged thriller is now available on Blu-Ray, DVD and digital download from Sony Pictures Home Entertainment.