Jamie Foxx Transforms into Mike Tyson for Upcoming Biopic: 'The First but Biggest Task'

Jamie Foxx is bulking up in a big way for his latest film project.

On Friday, the actor shared a series of photographs of himself sitting atop a short flight of stairs, showing off an impressive set of arm muscles. In the caption, he said the bulging bicepts are part of his "transformation" into legendary boxer Mike Tyson for the upcoming biopic Finding Mike.

"A few months ago we started the journey … The first but biggest task is to transform the body ... with a regiment of pull-ups dips and push-ups we are off to a pretty good start," wrote Foxx, 52. "We have a ways to go but God willing."

"Yesterday on my good friends @markbirnbaum show I shared these early pics of the process ... like I said we have a ways to go … But I am prepared to get there!" he added.

Many celebrities left supportive comments. Justin Timberlake left a strong-arm and firecracker emoji, and former professional boxer Oscar De La Hoya wrote, "There couldn't have been a better actor/person to play the legend. Congratulations my man."

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Foxx confirmed the movie was in the works while on Mark Birnbaum's Instagram Live series Catching Up on Wednesday, giving a "definitive yes" and saying, "Look, doing biographies is a tough thing. Sometimes it takes 20 years to get them done. But we officially got the real ball rolling."

The Oscar-winning star said he was eager to show audiences the "different lives" of the iconic boxer. "We want to show everybody evolves," he said. "I think when we lay the layer of Mike Tyson in this story, I think everybody from young and old will be able to understand this man's journey."

Foxx also touched on how he'd approach playing Tyson, saying, "And then just the technology of how I'm gonna look, I guarantee you people will run up on me in the street, and ask for autographs, and think that I'm Mike."

He continued, "Every other day, I do 60 pull-ups, we do 60 dips, we do 100 push-ups. I ain't got no calf muscles, so we might have to get some prosthetics for that."

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Bare Knuckle Fighting Championship offered Tyson, a 53-year-old former world heavyweight champion, a whopping $20 million last month to compete in a single fight for the organization.

"I think I know what we need to do to make this thing happen," BKFC President David Feldman told MMA Fighting, adding that the exact value of the contract was still being finalized.

"We're not successful yet in making that Mike thing happen. But I don't think the door's shut," Feldman added. "He did say no immediately. But I think there's room there."

Tyson began his career in 1985 and ended it in 2005 with a record of 50 wins, six losses and two no contests. Forty-four of his wins came by knockout. He retired from professional boxing in 2006.