See Mary Poppins Returns in theatres December 19! In Disney’s “Mary Poppins Returns,” an all new original musical and sequel, Mary Poppins is back to help the next generation of the Banks family find the joy and wonder missing in their lives following a personal loss. Emily Blunt stars as the practically-perfect nanny with unique magical skills who can turn any ordinary task into an unforgettable, fantastic adventure and Lin-Manuel Miranda plays her friend Jack, an optimistic street lamplighter who helps bring light—and life—to the streets of London.