Don Cheadle Learned Trumpet for Miles Davis Movie

— -- Don Cheadle wrote, directed and starred in "Miles Ahead," a non-traditional biopic about jazz legend Miles Davis.

He said the whole project was a real labor of love. That's why he decided to actually learn how to play the trumpet, just as Davis did.

"It was important to me to learn how to play because at some point in my development, Miles was as bad as I am now," he laughed. "Maybe he was 8 or 9 years old."

"I just wanted to be as close to him as possible and not just to do some kind of a Vegas mimicry," Cheadle told ABC News, "Try to understand him as much as I could."

Before Cheadle even knew, the "House of Lies" star was hand-picked by Davis' family to play the musician.

"It was a declaration that [Miles' nephew] Vincent made when Miles was inducted into the Rock and Roll Hall of Fame in 2006," Cheadle explained. "They were going to do a movie about his life and I was going to be the guy who played him."

"He hadn’t called me to ask first and I had never actually met him before," Cheadle continued. "That was something that he determined and then we set about trying to figure out what it would look like."

Cheadle adds that the whole project was challenging because he was directing himself, as well as the entire cast.

"Directing me wasn’t as tricky, I think, as directing the other actors," he explains. "You're not usually in scenes with actors who, once someone says 'cut,' look to you and go, 'OK...I think maybe you need to push that moment a little more.' And you're like, “Who’re you talking to? You’re just an actor. Don’t talk to me like that!'”

"Miles Ahead" opens in limited release Friday.