How the Stars of the Original Felt When They Stepped Onto the Set of 'Mary Poppins Returns'

The OG supernanny drops back in on the kids of Cherry Tree Lane in "Mary Poppins Returns," but she's not the only familiar face in the new Disney film.

While Emily Blunt takes over the title role made famous by Julie Andrews -- who opted against a cameo so Blunt could really shine -- two stars from the 1964 family film do still pop up in the long-awaited sequel.

Dick Van Dyke's Bert may be MIA, but he does appear as the son of bank director Mr. Dawes, another character he played in old age makeup back in the day. Also making the briefest of cameos was Karen Dotrice, who starred as the original Jane Banks. This time around, her character is being played by Emily Mortimer.

"It was extraordinary," Mortimer said of having Dotrice on set during a recent press day for the project. "She's such a great, cool lady, so funny, wicked sense of humor, really down to earth and ballsy and she came to do the cameo as a little moment where [costar Ben Whishaw] is emerging from the house with his briefcase late and he bumps into her and we're out together."

"We all walked on to the set for the first time with her and she walked on to Cherry Tree Lane for the first time in 54 years or however long it has been since the first movie was made and she just melted," Mortimer continued. "I mean she just sort of crumbled and that was so moving being there with her while that happened and seeing that."

According to director Rob Marshall, having Van Dyke -- now 93 and still busting a move -- on set was equally moving.

"I mean every one of us was there and it was beyond," he recalled. "I don't think any of us could even breathe that day because we couldn't believe that we were touching that. He grabbed my hand as we walked on to the set and he turned to me and he said something I will never forget. He said, 'I feel the same spirit here on this set that I did on the first film.' And that was, you know, that was the dream come true right there."

Of course, the filmmakers didn't want the entire movie to be a callback to the original. While there are moments that will no doubt leave viewers feeling nostalgic -- like Lin-Manuel Miranda's "Step In Time"-inspired "Trip the Light Fantastic" and another stunning animated sequence -- it was a delicate "balancing act" to keep things feeling fresh.

"I really felt that everyone who was a part of this needed to have the first film in their blood in some way because that's what we were following," explained the director. "And so we were looking for that balance throughout the entire time we were working on this film and I use myself as a barometer. I thought well, what would I want to see?"

"If I came to a sequel to Mary Poppins I would want to see an animation sequence with live action and I would want it to be hand drawn in a 2D world," Marshall continued. "I would want to see that. I would want Cherry Tree Lane to have a curve to it because that's the Cherry Tree Lane we all know. I would feel disappointed if it was a straight street. I mean it was as simple as that, although we were finding our new way."

Moving the movie into the '30s and focusing the story on the now-adult Michael and Jane Banks helped distinguish between the two projects.

"It was constantly back and forth and I have to say I just used my own gut about what needed to be there, what we needed to reflect, pay homage," added Marshall, who also said they restrained themselves from using the original movie's theme music until the end, where they felt they "earned it."