Mark Wahlberg, an actor typically known for being one of the industry’s most reliably buff action heroes, has revealed in a new interview that he’s set to pack on 30 pounds to play boxer-turned-priest Father Stuart Long in upcoming biopic Father Stu. The utterly fascinating true-life story will co-star Mel Gibson as Wahlberg’s onscreen father for the second time after comedy sequel Daddy’s Home 2, and Gibson’s longtime partner Rosalind Ross wrote the script on which she’ll also make her feature directorial debut.

Narcos: Mexico star Teresa Ruiz is also on board as Long’s girlfriend, and per a report from The Hollywood Reporter, it’s a movie Wahlberg has been trying to get made for several years now. He was once attached to the project with an eye to having David O. Russell direct, but Ross has been working on the script for a while, having become something of a popular script doctor in the industry since gaining recognition for her 2016 script Barbarian, which ended up on the Black List.

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Image via HBO Max

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In a recent appearance on Jimmy Kimmel Live, Wahlberg revealed that production is set to begin on Monday with all of the boxing scenes getting taken care of first, before he gets the chance to binge eat whatever he wants in order to gain the necessary poundage.

“After we do the boxing scenes, I get to put on as much weight as possible over the course of the film, so I’m challenging myself to put on 30 pounds in the next six weeks. ... They want me to do it as healthy as possible and I’m like ‘Dude, I’ve been on such a regimen for so long, I just want to eat everything in sight. ... I want to go to bakeries. I want to go to Denny’s. I want to get pancakes. I want to get everything I can possibly get my hands on.”

The real Stuart Long’s boxing career ended after a broken jaw, so he moved to Los Angeles to try and get into the movie business before suffering a horrific motorcycle accident that saw him hit by one car and then run over by another. During his recovery in the hospital, he claimed to have had an out-of-body spiritual experience, leading to him enlisting in an Oregon seminary. While studying for the priesthood, he was diagnosed with a rare degenerative muscle disease and couldn’t walk unassisted by the time he was ordained, and his condition worsened to the extent that he spent his final years in a motorized chair before passing away in 2014.

Wahlberg might be best known for his string of mid-budget action thrillers, but he also landed an Academy Award nomination for Best Supporting Actor in The Departed, and his last boxing drama saw him score a second Oscar nod after he produced The Fighter, which was shortlisted for Best Picture. Based on the incredible story of Father Stu’s life, it sounds like an awards-caliber role and perhaps even a career-defining performance from Wahlberg. Watch the full Jimmy Kimmel Live interview with the actor below.

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