Dwayne Johnson, best known worldwide as “The Rock,” has stepped into one of the most ambitious roles of his career with The Smashing Machine.

In an interview with CBS News’ Sunday Morning, the actor opened up about portraying real-life MMA champion Mark Kerr, a two-time world titleholder who battled addiction and depression. The role required Johnson to undergo three hours of daily makeup and prosthetics, marking one of his most transformative performances. “For years, I’ve been dreaming and hoping,” Johnson said. “I wanted to play something that really allowed me to rip myself open.” The film also stars Emily Blunt as Kerr’s wife, Dawn Staples. Johnson admitted he was nervous about taking on the raw, emotionally heavy role but leaned into past hardships for inspiration, recalling his family’s eviction at age 15. “That feeling of despair – I went right back to it,” he said.

With The Smashing Machine’s success, Johnson says this role marks “a whole new book” in his career.