How Julie Andrews made a cameo in 'Aquaman' but not 'Mary Poppins Returns' (SPOILERS!)

Warning: This post contains spoilers for Aquaman and Mary Poppins Returns.

Facing a choice between Aquaman and Mary Poppins Returns this holiday weekend, moviegoers chose Aquaman, powering the latest DC Comics-based movie to a $72 million opening compared to Mary‘s $31 million. Believe it or not, Dame Julie Andrews had to make a similar decision … and she also chose the guy who talks to fishes over the umbrella-carrying nanny.

Aquaman‘s James Wan and Mary Poppins Returns‘ Rob Marshall separately approached the legendary British actress — and the original Mary Poppins — to appear in their respective movies. Marshall has since said that Andrews turned down his offer out of respect for Returns star Emily Blunt. (If you’ve seen the movie, it’s fairly clear that another British screen icon, Angela Lansbury, took the cameo role meant for Andrews.)

But there was nothing holding Andrews back from lending her pipes to Aquaman. The actress voices an ancient sea creature known as the Karathen, whom half-Atlantean/half-human Arthur Curry (Jason Momoa) must confront before claiming his trident and, with it, the throne of Atlantis. It’s not exactly the kind of character you’d picture for a grand dame of Hollywood, but that’s what attracted Wan to the idea. “Going into the casting of that role for some reason I wanted the creature to be female and British,” the director explains to Yahoo Entertainment. “Julie’s name came up and I was like, ‘That would be incredible. The most powerful creature on this planet is a dame.'”

Audiences won’t be the only ones to be surprised when Andrews’s names appears in the Aquaman‘s credits. The movie’s cast had no idea about Wan’s cameo coup, either. “I thought that was pretty cool,” Momoa says, smiling. That meant they didn’t get to attend the recording session where Wan had the opportunity to direct Andrews. To help her get into character, he told her: “To play [Karathen] as someone who hasn’t spoken anyone in over thousands and thousands of years, so you can imagine how kind of cranky your character would be!” You know what helps crankiness? A spoonful of sugar…

Aquaman is playing in theaters now.

Watch: Rob Marshall reveals his favorite Easter eggs in Mary Poppins Returns:

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