Zac Efron's The Iron Claw preparation inspired ice bath scene in A Family Affair

Zac Efron's physical preparation for The Iron Claw helped inspire a scene in his new romantic comedy A Family Affair.

The High School Musical star was preparing to play wrestler Kevin Von Erich in the biographical drama while shooting the rom-com with Nicole Kidman and Joey King.

After squeezing in workouts, Efron often sat in an ice bath by his trailer, and this practice ended up working its way into a scene in A Family Affair.

"A lot of the stuff that I was doing in preparation kind of worked its way in (A Family Affair)," he told People. "Like the ice bath was just in front of my trailer. I was constantly doing it because I was so sore.

"(Director Richard LaGravanese) came to give me some notes over lunch and I was in the ice bath the whole time, shivering while he was telling me notes. He was like, 'Dude, we have to put this in the film.' Then the next scene, we just did like a 20-minute ice bath (scene with) Joey."

In the new film, Efron plays an egotistical movie star who starts dating his personal assistant's mother.

The actor told the outlet that the original title of the film, Motherf**ker, immediately caught his attention in his pile of scripts.

"That made the script stay at the top of the pile. It's like, what on earth could this be about?" he shared.

A Family Affair is now streaming on Netflix. The Iron Claw was released in the U.S. last year.