Zac Efron Details His 'Shocking' Physical Transformation for 'Iron Claw' Role

Zac Efron portrays Kevin Von Erich in the new movie The Iron Claw, and he went above and beyond to look the part. In an interview with Entertainment Tonight at the premiere on Wednesday, Efron said that he was shocked the first time he saw himself in full costume. However, Efron said his hesitation didn't last long as the finished product began to take shape.

Efron was with the real-life Kevin Von Erich in Dallas, Texas on Wednesday when he spoke to ET. He said: "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."

Efron has always been in good shape as a leading man, but he visibly bulked up for this role. However, he said that the real surprise came when he saw himself with Erich's signature bowl cut in 80s wrestling attire. He said: "It was shocking at every point of the transformation. I remember Harris [Dickinson] 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."

So far, Efron's favorite reaction to the film has come from Kevin Von Erich himself. Efron said: "He told me he was happy with it last night, so I'm stoked! I cried a little bit, if I'm going to be completely honest."

The Iron Claw is a dramatization of the real lives of the Von Erich family – a professional wrestling dynasty that rose to prominence in Texas in the 1980s in part for popularizing the "iron claw" hold. While the family fought for their success in the ring, they dealt with a shocking slew of personal tragedies in their day-to-day lives.

Alongside Efron, stars include Harris Dickinson as David Von Erich and Jeremy Allen White as Kerry Von Erich. The movie was written and directed by Sean Durkin and produced by A24. Sadly, after Wednesday's premiere fans will have to wait quite a while to see it for themselves. The Iron Claw is slated to hit theaters on Dec. 22.