Max Casella.Photo: Jamie McCarthy/Getty Images

Max Casella attends a screening of “The Tender Bar” hosted by Amazon Studios at Museum of Modern Art

Max Casella is opening up about not experiencing puberty until his late 20s.

The actor, 55, toldPage Sixthat he haspituitary dwarfismandwas 27 when he hit puberty.

Being candid about the condition, Casella described it as “a horror show,” adding, “I couldn’t talk about it. No one understood it. It’s like the trans community today talks about body dysmorphia and feeling like, ‘I’m in the wrong body,’ absolutely my experience. Absolutely. I was a man trapped in a little boy’s body throughout most of my 20s until they finally pumped me full of testosterone.”

In an exclusive interview published Friday, Casella told PEOPLE howappearing younger than he really wasimpacted his acting career.

In his late 20s, the actor found himself struggling to book the kind of roles he had aspired to. “Show business can just step all over your heart,” he said matter-of-factly.

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Casella, who found early momentum in films like 1992’sNewsieswithChristian Baleand 1996’sSgt. BilkowithSteve Martin, felt at the time it was movie stardom or bust. But in the process, “I got away from all the studying I had done about acting,” he admitted.

Now he stars oppositeSylvester Stallonein the new mob dramaTulsa King(premiering Sunday on Paramount+), playing a recovering gangster hiding out in Oklahoma. Casella called the project “the greatest experience of my career” — in part due to the richly developed character he plays.

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InTulsa King,Casella portrays “a guy who’s been running his whole life and pretending to be something he’s not,” who is forced to face his past when Stallone’s mobster suddenly moves to town.

Working with Stallone “was like a dream come true,” Casella said. “I had his poster on my wall when I was 10. He was everything you would want him to be.”

source: people.com