Oscar-nominated Call Me by Your Name director Luca Guadagnino will helm the project, with Mara producing and The Giver co-writer Michael Mitnick penning the script.
Though plot details are being kept under wraps, Hepburn is an acting legend celebrated for her performances in classics like Breakfast at Tiffany's, My Fair Lady, Wait Until Dark, Charade and Sabrina. During her four-decade career, Hepburn achieved EGOT status, winning Emmy, Oscar, Tony and Grammy awards, the last of which she received posthumously. She was also a dedicated humanitarian, working with UNICEF to help children in Africa, South America and Asia and receiving the Presidential Medal of Freedom in 1992.