The adaptation is written by Dan Gordon. The production will be designed by Jonathan Fensom, with lighting by Jason Taylor. The show will co-star Adam Godley, Colin Stintinto, Mary Stockley, Charles Daish, and Tilly Blackwood.

The work focuses on Charlie Babbitt, a self-centered Los Angeles-based car dealer and hustler, who must suddenly care for Raymond, the elder brother Charlie never knew he had, an autistic savant who's been hidden away in an institution for most of his life.

Hartnett, who will play Charlie Babbitt, is best known for films such as Pearl Harbor, Black Hawk Down, and The Virgin Suicides. Godley will play Raymond, received Olivier nominations for Emmanuelle and Dick and Mouth to Mouth.