Zac Efron says getting real-life wrestler Kevin Von Erich’s blessing for ‘The Iron Claw’ was the “most important review” he could get for the biopic.

The 36-year-old actor plays Kevin in the film about the showman’s family’s rollercoaster dynasty, and threw himself into the role by undergoing a physical transformation and sporting bowl cut hair.

Zac told Variety about meeting the retired wrestler, 66, the night before the Dallas premiere of the film: “I was very curious about what he thought of the movie.

“We went out to the patio, sat forehead to forehead, and talked about life for an hour and a half.

“And he told me that he did enjoy the movie. I can’t really put into words how that feels.

“It’s far and away the most important review to me on so many levels. It meant the world, and everything just came full circle.”

Zac has told Entertainment Tonight about his physical overhaul for the movie: “It was shocking at every point of the transformation. I remember Harris (Dickinson, who plays Kevin’s brother in the film) and I were walking out of hair and make-up and it was like the first time we had to wear the full kit, and we were both thinking, ‘What the hell are we doing here, man? How did we get into this?’

“But I think it ended up looking really good and we had a great crew helping us out with that. The hair and make-up team was epic.

“This movie’s a true story, and that man, Kevin Von Erich right there, he really motivated me to get in shape for this movie.

“The physicality he brought to the ring every single day was really unique. It changed wrestling.

“I knew that was going to be the hardest (thing) for me to master and get right. So, I put everything I had into it.”

The film follows the Von Erichs, led by father and coach Fritz Von Erich (played by Holt McCallany) and his sons Kevin, David (portrayed by Harris), Kerry (Jeremy Allen White) and Mike (Standley Simons.)

The wrestling dynasty as hit by a string of suicides and illnesses, with Kevin’s brothers all dying before their father – sparking reports of the ‘Von Erich curse’.