Zac Efron says cast chemistry makes The Iron Claw a special film

Zac Efron says 'The Iron Claw' is a special film because the cast's chemistry was "off the charts".

The 36-year-old actor plays Kevin Von Erich in the biographical sports film about the professional wrestling family the Von Erichs, directed and written by Sean Durkin.

Zac stars in the movie with Jeremy Allen White, Harris Dickinson, and Stanley Simons, and he quickly got the feeling that they were all contributing to something remarkable because of their commitment to the true story.

He told website HeyUGuys: "We got to know each other really well before we got started and you could tell that all these actors really care deeply about this story. So, I mean, if you've got committed, hard-working, smart, cool guys around you, your chemistry is off the charts. So, love those guys.”

To prepare for his role as '80s grappling champion Kevin, the ‘High School Musical’ actor trained with former WWE Superstar Chavo Guerro - the nephew of late wrestler Eddie Guerrero - to get ring ready.

Zac and his co-stars were put through their paces between the ropes by Chavo, 53, and quickly learned that wrestling is one tough sport.

He said “We dropped our egos at the door and just started to listen. And we had a great coach in Chavo Guerrero. I mean wrestling is no joke. It’s a hell of a sport.”

The family was blighted by the "Von Erich Curse" with Kevin's brothers, wrestlers David, Mike, and Kerry, all dying young.

Kerry - known as the Texas Tornado when competing in Vince McMahon's WWE promotion in the '90s - took his own life when he was just 33, while David passed aged 25 in mysterious circumstances during a tour of Japan in 1984. Mike also ended his own life by overdosing on sleeping aid Placidyl and alcohol when he was just 25, leaving behind a tragic note for his family.

The family's problems with toxic masculinity and mental health issues are depicted in 'The Iron Claw' and Zac says the film does an important job of showing the devastating effects on the siblings at a time when these matters were not discussed.

Zac said: “It’s interesting yeah, because there’s not really language around it at this point. It’s how it sneaks up on you, and in the case of the Von Erichs, it’s just such a brilliant example of how it kind of works its way into, you know, successful careers and strong families and things like that, it really is a fascinating look.”