Who would dare write the songs for Mary Poppins Returns ... Lin-Manuel Miranda astonished the theatre world by telling the story of Alexander Hamilton partly through rap music.

Now viewers can get a rare behind-the-scenes look at the movie’s making and legacy courtesy of 20/20, with The Untold Story of Mary Poppins airing on Wednesday, November 27, at 9 pm ET/PT on ABC.

It's been 60 years since the Disney classic "Mary Poppins" first floated into our lives. For a while, making the film seemed like an impossibility for Walt Disney. He pursued the film rights from ...

PHOTO: Robert and Richard Sherman work on the soundtrack for the Disney classic 'Mary Poppins.' (Disney) This song was also key in winning over Travers, who met the Shermans at story meetings at ...

Watch the "20/20" special edition "The Untold Story of Mary Poppins" airing at 9 p.m. Wednesday, Nov. 27, on ABC, and streaming the next day on Disney+ and Hulu. As Poppins takes her young wards ...