Emily Blunt Is Practically Perfect in the Mary Poppins Returns Trailer

Colin Firth, Angela Lansbury, Lin-Manuel Miranda, Emily Mortimer, Meryl Streep and Ben Whishaw star in the movie musical

Emily Blunt proves that "in every job that must be done, there is an element of fun."

Walt Disney Studios just released the first full-length trailer for Mary Poppins Returns (in theaters Dec. 19), featuring Blunt taking over the role Julie Andrews made famous in 1964. The footage opens with Mary descending from the clouds and visiting the grown-up Banks kids. Michael (Ben Whishaw) marvels, "You seem hardly to have aged at all." Aghast, Mary replies, "Really? One never discusses a woman's age, Michael. Would have hoped I taught you better."

Michael's sister, Jane Banks (Emily Mortimer), is just as astonished by her nanny's arrival. But as a recent widower, Michael—and more, importantly, his children—need her more than ever.

Keep an eye out for award-winning actor Lin-Manuel Miranda as Mary's friend Jack, described as "an optimistic street lamplighter who helps bring light—and life—to the streets of London." Other cast members include Pixie Davies, Joel Dawson and Nathanael Saleh and as the Banks' children; Colin Firth as Fidelity Fiduciary Bank's William Weatherall Wilkins; Angela Lansbury as the Balloon Lady; Meryl Streep as Topsy, Mary's eccentric cousin; Dick Van Dyke as Mr. Dawes, Jr., the retired chairman of the bank; and Julie Walters as the family's housemaid, Ellen.

The full-length trailer debuted on ABC's Good Morning America.

Rob Marshall directed Mary Poppins Returns, from a screenplay by David Magee (based upon the Mary Poppins Stories by P.L. Travers.) Marshall also produced the movie with John DeLuca and Marc Platt, with Callum McDougall serving as executive producer. Marc Shaiman, who handled the score, also created original music for the film and wrote lyrics with Scott Wittman. The trailer shows Blunt singing one of the new songs—and it's supercalifragilisticexpialidocious.

The first teaser trailer for Mary Poppins Returns was released in March.

Blunt talked to E! News about becoming Mary last year. "I think I did have a 'nerdgasm' when I put on the costume. Sandy Powell designed the costumes, which are stunning," she raved. "I love that Mary Poppins is vain and stylish and into herself; it was enjoyable to sashay around in Sandy Powell's creations." As for her take on the role, she said, "I needed to try to pay homage to Julie Andrews, but carve out a new space for myself—and we were very loyal to the books."

In that way, Blunt is like Mary: "Practically perfect in every way."