Anthony Robles Says the 'Scariest Part' of Unstoppable Adapting His Incredible Wrestling Story Was 'That Loss of Control' (Exclusive)

The new wrestling drama Unstoppable is based on the remarkable real-life story of a man born with one leg who fights his way to becoming an NCAA champion. For its subject Anthony Robles, seeing his story on the big screen is a complicated — and cathartic — process. 

“I tried to hold my emotions in as much as I can, but it was just an instant wave at the very end,” he tells PEOPLE of seeing the movie premiere on Friday, Sept. 6 at the Toronto International Film Festival. 

Robles, 36, “had a moment” at the screening with his mother, Judy, played onscreen by Jennifer Lopez. “It just hit us and both of us, we were crying,” he admits. “I just couldn't be happier, to be honest with you.”

Entrusting the filmmaking team, which includes director William Goldenberg and producers Ben Affleck and Matt Damon, to adapt the bestselling memoir he co-wrote with Austin Murphy required a leap of faith, Robles tells PEOPLE.

“The scariest part for me is that loss of control and having faith,” says the Arizona native, sitting alongside cast members Lopez, Jharrel Jerome, Bobby Cannavale and Don Cheadle the day after the starry premiere. “But with this amazing group of individuals, we knew we could trust them and we knew that the integrity of the story, the message of it, and my family would be safe with this group.”

The Robles family’s story, adapted by screenwriters Eric Champnella, Alex Harris and John Hindman, navigates Anthony's determination to make the Arizona State University wrestling team as the family coped with his mother Judy's often abusive relationship with his stepfather (played by Cannavale).

“It was told so beautifully,” Robles says. “It respected what we went through, but also at the same time it captured where our strength came from.”

For lead actor and producer Jerome, 26, the scariest part of filming was portraying Robles accurately onscreen. “I've been involved since 2019,” the When They See Us Emmy winner says of Unstoppable. “This is basically my first time where it's gone far beyond the character that I'm trying to become. Anthony and I have built a friendship. I've gone to his home in Arizona. I've spent time with him in his backyard grilling with his family.”

That close connection “informed a lot of the performance,” says Jerome. “Just kind of watching his mannerisms and staying quiet.” 

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The hardest part of playing Robles at the peak of his wrestling career? While difficult for Jerome to pinpoint “between the gym and the diet and the sleeping and the lifting,” it may be the calluses under his armpits from walking so often with crutches like the real athlete. 

“And then of course the wrestling, wrestling on the ground,” recalls the actor, who is doubled in parts of the film by Robles himself. “Anthony has such a specific style of wrestling, so it wasn't like I showed up to wrestling class and I was learning the basic, cookie-cutter grappling moves. I was on the ground and having to practice how to move on my hands, how to slide on my knees.”

Overall, "the most important thing was to do right by Anthony and his family," echoes Goldenberg, who directed the film. At the Toronto premiere, he adds, seeing the joy on Anthony and Judy's faces, "I just felt like this tremendous relief because you have somebody's whole life in your hands."

Unstoppable, from Amazon MGM Studios, will be in limited theaters this December and streaming on Prime Video. The Toronto International Film Festival runs through Sept. 15.