Lin-Manuel Miranda on 'Thrilling' 'Moana,' 'Hamilton' Documentary and More

— -- Lin-Manuel Miranda is everywhere these days. The "Hamilton" composer hosted “Saturday Night Live” last weekend and the premiere of the much-awaited “Hamilton” documentary airs on PBS next week.

Miranda, 36, is also preparing for the release of “Moana,” the Disney animated movie whose music he composed, and packing for London, where he will spend the next year filming “Mary Poppins Returns.”

Miranda said today on “Good Morning America” that after the show he would be “packing boxes” for London. He will play in “Mary Poppins Returns” a role similar to the one made famous by Dick Van Dyke in the original “Mary Poppins” movie, but with a twist.

“This takes place about 20 years after the original Mary Poppins film took place but I get to be around for the adventures with Mary and the kids and sing and dance and do all the fun things,” said Miranda, who will co-star with Emily Blunt in the Rob Marshall-directed film. “There are about eight Mary Poppins books so what the creative team has done is sort of taken some of the adventures from those.”

For “Moana,” Miranda had to figure out how to give voice to Dwayne “The Rock” Johnson, who voices the character Maui, the great ocean demigod who helps fearless Moana as she embarks on an epic adventure to discover what is beyond the confines of her island.

“I didn’t know if he could sing so I went on YouTube to sort of find any examples of The Rock singing and what I found was this super cut when he was a bad guy wrestler,” Miranda said. “He would take out a guitar and taunt whatever town he was in."

Miranda described working on the movie, in theaters Nov. 23, as “thrilling” and said writing for Johnson ended up being especially fun.

“The fun thing about writing for The Rock is he’s so charming you can give him Gaston-level arrogant lyrics and it’s still charming,” he said, referring to the villain in “Beauty and the Beast.”

“Hamilton,” the Broadway musical that thrust Miranda into the spotlight, will get its own turn in the spotlight again when the documentary “Hamilton’s America,” premieres on PBS on Oct. 21.

Miranda, who famously wrote the rap musical about the nation’s founding fathers after reading a biography of Alexander Hamilton by Ron Chernow, said a friend from college began filming him at the start of his long road to Broadway.

“The film is directed by Alex Horowitz who I actually went to college with and he started filming me before I even knew this was going to be a play,” Miranda said. “He said, ‘I don’t know what this is going to be but it’s going to be cool. Can I just start filming you?’"

Miranda continued, "He’s got footage of me writing ‘My Shot’ in Aaron Burr’s bedroom. He’s got footage of me moving into our apartment. It’s sort of the journey that I took writing the show, the journey of Hamilton and the journey of ‘Hamilton’ the musical sort of all in one."

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