Dwayne "The Rock" Johnson transforms into MMA and UFC fighter Mark Kerr in Benny Safdie's A24 biopic "The Smashing Machine," releasing this fall.

Dwayne Johnson stars as former wrestler and UFC star Mark Kerr in a new trailer for Benny Safdie's "The Smashing Machine."

Dwayne Johnson will portray Mark Kerr in "The Smashing Machine." The film explores Kerr's MMA career and personal struggles. Kerr was a UFC champion known as 'The Smashing Machine'. His career was marked by substance abuse and health issues.