Who is The Rock? How prosthetics transformed Dwayne Johnson into Mark Kerr in “The Smashing Machine”

To bring MMA fighter Mark Kerr to life on screen, Dwayne Johnson had to vanish behind a carefully crafted disguise. "It demanded complete immersion," Johnson told Entertainment Weekly, describing the challenge of leaving behind his iconic WWE image for the biopic. "The goal was total disappearance."

For this physical metamorphosis, Johnson collaborated with renowned prosthetic designer and special effects artist Kazu Hiro. Hiro created 22 distinct prosthetic pieces for the actor, including modifications to the eyes, nose, cauliflower ear, and scars. The full application took roughly three and a half hours, a painstaking process captured in a timelapse video accompanying the films coverage.

Hiro, whose work spans films such as Looper, Salt, G.I. Joe: The Rise of Cobra, Angels & Demons, Norbit, and The Haunted Mansion, explained that this project presented unique difficulties. "Dwayne is instantly recognizable," he said. "Everyone knows his face, so the challenge was to create a believable Mark Kerr while still retaining Dwaynes essence."

Hiro emphasized the importance of balancing authenticity with functionality. "The actors expressions must remain visible through the prosthetics," he said. "If something differs too much from the real person, it cannot hinder the performance. Our aim was to keep the application time manageable while ensuring the prosthetics were functional."

Unlike other biopics, The Smashing Machine includes intense fight sequences. This meant that the prosthetics needed to endure punches, sweat, and repeated wear. After fights, injuries had to be recreated with new prosthetics layered over the original ones, each designed for single use. Hiro studied archival footage and the 2002 documentary The Smashing Machine: The Life and Times of Extreme Fighter Mark Kerr to accurately portray facial injuries and healing stages.

The hair and makeup team numbered 25 to 30 people. While Hiro focused on the prosthetics, Glen Griffin handled their application, Oscar-winning hairstylist Mia Neal designed the Mark Kerr wig, and other specialists covered Johnsons tattoos before painting on Kerrs.

"What I love most is the trust that builds during this process," Hiro said. "Seeing the actors reaction in the mirror at the end of the day is incredibly rewarding. Ultimately, we rely on a great actor to make our work effective."

Hiro also admitted he is his own toughest critic. "I rarely feel satisfied with my work," he said. "Even when others are impressed, I keep analyzing and learning. Thats how we improve."

Author: Benjamin Carter