When Walt Disney’s daughters begged him to make a movie of their favorite book, P.L. Travers’ “Mary Poppins,” he made them a promise — one that he didn’t realize would take 20 years to keep. In his quest to obtain the rights, Disney comes up against a curmudgeonly, uncompromising writer who has absolutely no intention of letting her beloved magical nanny get mauled by the Hollywood machine. But, as the books stop selling and money grows short, Travers reluctantly agrees to go to Los Angeles to hear Disney’s plans for the adaptation. For those two short weeks in 1961, Disney pulls out all the stops. Armed with imaginative storyboards and chirpy songs from the talented Sherman brothers, Disney launches an all-out onslaught on Travers, but the prickly author doesn’t budge. He soon begins to watch helplessly as Travers becomes increasingly immovable and the rights begin to move further away from his grasp. It is only when he reaches into his own childhood that Disney discovers the truth about the ghosts that haunt her, and together they set Mary Poppins free to ultimately make one of the most endearing films in cinematic history. Extras: Deleted scene “Nanny Song,” in which the Sherman Brothers composers perform a song that P.L. Travers is less than thrilled about. Blu-ray adds two more deleted scenes, “The Walt Disney Studios: From Poppins to Present” featurette, “Let’s Go Fly a Kite” in which the cast and crew sing break out in a rousing, heartfelt tribute to composer Richard Sherman on the last day of filming. Vitals: Director: John Lee Hancock. Stars: Emma Thompson, Tom Hanks, Colin Farrell, Paul Giamatti, Jason Schwartzman, Bradley Whitford, Annie Buckley, Ruth Wilson, B.J. Novak, Rachel Griffiths, Kathy Baker. 2013, CC, MPAA rating: PG-13, 125 min., Bio-Drama, Box office gross: $81.877 million, Disney.