Becoming the iconic music legend James Brown isn’t easy. He’s a man defined by his mannerisms, his unique way of speaking, and his overall personality. The way James Brown acted was so identifiable, his behavior became the focus of Tate Taylor’s biopic Get On Up (2014). And the actor who brought that persona to the screen to great critical acclaim was Chadwick Boseman, who just the year before successfully resurrected Jackie Robinson on film in Brian Helgeland’s 42 (2013).

The one thing Boseman didn’t have to do in Get On Up was sing. The filmmakers used actual James Brown audio tracks for all of the musical scenes. As such, all Boseman had to worry about was the behavior, speaking voice, dancing style, swagger, general mannerisms, physical appearance, and charismatic attitude of the funk legend.

“I felt like nobody should do this,” Boseman told “Nightline. “I went online and looked at footage of him dancing, and I was like, ‘absolutely not… there’s no way.”

Boseman had no formal dance training. He has a BFA in Directing from Howard University, and studied at the British American Drama Academy. Writing and directing were his intended paths, and as he told The Washington Post, “I really only started acting because I wanted to know what the actors were doing, and how to communicate with the actors.”

Now he’s become a great one.

To transform into James Brown, Boseman had to meticulously study videos of Brown’s dancing and mannerisms, and understand the way they changed and developed over time. He also spent 5-8 hours a day with a choreographer learning to dance like James Brown, five days a week, for two months.

“I think the hardest thing was the groove, you know, James Brown’s groove,” Boseman said. “Once you get that, you sort of understand the rest of it.”

Working with choreographer Aakomon Jones, Boseman set up a series of mirrors that would reflect isolated parts of his body, which allowed him to concentrate on honing the movements of specific sections individually to achieve an overall physical perfection.

Watching footage of the man’s superstar years and absorbing the physicality and musicality of everything is obviously important, but he felt learning about the little boy that came before the music is where the truth about the character lived. Boseman read anything he could find about Brown’s childhood life.

“It’s the thing that’s constant,” he told The LA Times. “It might be a different wife, it might be different band members, but the only constants are [band mate] Bobby Byrd and the little boy. And even Bobby Byrd is gone at certain points. … There’s a sense of abandonment that he has, and, in the young boy, there’s a sense of sadness and solitude. But being out there and having that imagination enabled him to make music. When he gets older, it does turn into loneliness. I think that’s the core.”

The film also spans decades of Brown’s life, requiring Boseman to wear an enormous amount of wigs, aging makeup, outfits, and body suits. Just as the film isn’t told in a chronological fashion, it wasn’t shot chronologically, which required the actor to constantly shift between Brown’s different versions of himself, remaining true to teach part of his life.

“There was a day where I was 55, 17, and then 35,” he said.

What resulted from all this character study and physical practice is a frighteningly realistic rendition of James Brown. Though Boseman didn’t receive any major award nominations for the performance, the hard work paid off, as he’s widely considered the driving force of the film.

And just in case Boseman wasn’t impressive enough already, even though he didn’t sing in the film doesn’t mean he can’t.