Hartnett is best known for his roles in the films "The Black Dahlia," "Lucky Number Slevin," "Pearl Harbor" and "The Virgin Suicides."
Variety.com said Hartnett will play Tom Cruise's narcissistic car dealer character in the updated stage version of the movie "Rain Man," while British actor Adam Godley will play his autistic savant brother, a character created on-screen by Dustin Hoffman.
The play is to begin preview performances Aug. 28, with an opening night planned for Sept. 9, the entertainment industry trade paper said.
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