Lin-Manuel Miranda makes his onscreen feature film debut with Disney’s Mary Poppins, and it's a first the Hamilton and In The Heights creator and star has been longing for his whole life.

What was it like to only worry about the acting? “In the Heights represents me sort of trying to make my way into this world I love so much, so to go from that and Hamilton to be offered a role like this, it feels like the fruit of that harvest,” he tells Playbill in the video above.

Miranda plays Jack, a “leery” in London—also known as a lamplighter. The same age as now-adult Jane and Michael Banks, Miranda sees Jack as a sort of protege of the original Mary Poppins’ Bert; he remembers the magic of Mary Poppins and holds onto that childhood hope.

“My biggest piece of research was my 2-year-old son,” Miranda confesses. “What we know about Jack is he’s the only adult who remembers the childhood adventures of Mary Poppins. He’s the same age as the Banks kids—he’s shining shoes outside while they’re up at Cherry Tree Lane. My biggest research assistant was my own son, who is coming into his own imagination as he grows up, and tapping into that.”

The actor also spoke about what he learned from Mary Poppins Returns director Rob Marshall that he plans to take to his film directorial debut, ticket...tick...Boom!, and how working on a movie set most differs from the world of Broadway. Watch the full video above.