The Oscar winner, 77, was tasked with playing a man in his thirties, forties, and fifties in Martin Scorsese's anticipated Netflix epic.

The number most associated with Martin Scorsese’s upcoming Netflix epic “The Irishman” is its growing price (once $100 million, then $125 million, now $140 million). But Scorsese really wants the film to dazzle with the number 39. On The Ringer‘s Bill Simmons Podcast, 77-year-old Pacino — who plays long-missing ex-Teamsters union leader Jimmy Hoffa — explained that he’ll spend parts of the gangster epic playing a character that’s about half his actual age.

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“I was playing Jimmy Hoffa at the age of 39, they’re doing that on a computer,” said Pacino, referencing the tech wizardry employed by Industrial Light & Magic. Pacino explained that computers mounted on the sides of cameras were programmed to capture the actors at various ages, making them appear physically transformed in every frame.

“We went through all these tests and things,” he continued. To achieve the most authentic performance possible, members of the crew would tip off the Best Actor Oscar winner (“Scent of a Woman”) as to how old Hoffa was in each scene. “Someone would come up to me and say, ‘You’re 39.’ [You’d recall] some sort of memory of 39, and your body tries to acclimate to that and think that way. They remind you of it.”

Digital Doman previously helped David Fincher reverse-age Brad Pitt in “The Curious Case of Benjamin Button,” while Lola VFX made Michael Douglas appear much younger in “Ant-Man.” More recently, visual effects supervisor Jay Worth helped Anthony Hopkins channel his past on “Westworld;” Ang Lee is enlisting more pioneering VFX for 2019’s “Gemini Man,” where Will Smith portrays a spy squaring off against himself.

“The Irishman” will be Pacino’s fourth collaboration with co-star De Niro, following “The Godfather Part II” (1974), “Heat” (1995), and “Righteous Kill” (2008). An adaptation of Charles Brandt’s 2003 true crime memoir, “I Heard You Paint Houses: Frank ‘The Irishman’ Sheeran and Closing the Case on Jimmy Hoffa,” the saga casts De Niro as veteran mob hitman Sheeran, who many believe was involved in Hoffa’s demise.

Scorsese announced the conclusion of filming March 5. Netflix will stream the result next year.

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