Just over a week from now, Julie Andrews will return to the big screen—not, as you may expect, to reprise her titular role in Mary Poppins Returns, which hits theaters across the U.S. on December 19, but instead to grace the cast of Aquaman in the underwater kingdom of Atlantis—in other words, about as far away from turn-of-the-century London as you can get. Quite unlike her former costar in the original Mary Poppins, Dick Van Dyke, who graciously accepted the offer of a cameo in the sequel at the ripe old age of 92, Andrews formally bid farewell to the realm of make-believe, giving Emily Blunt her blessing to pick up her old umbrella and take over as nanny, this time alongside Lin-Manuel Miranda and Meryl Streep.

The timeline, however, hints that there was a bit more at play behind the scenes. Jason Momoa, you see, was announced to star in Aquaman all the way back in October of 2014, and the film's other stars, Amber Heard and Nicole Kidman, were confirmed to join him in early 2016 and 2017, respectively. And as for Andrews, the film's only Oscar-winning star who's also earned the title of Dame? The news that she would be diving into the DC Extended Universe right along with them only broke less than a month ago—almost exactly a year and a month to the day that filming apparently wrapped.

Julie Andrews playing the titular role in Mary Poppins, 1964.

© 1964 Walt Disney Productions

So, why did Andrews's involvement stay silent for so long? The reviews of Aquaman that hit after embargo lifted on Tuesday, appear to offer a few clues. Previously, all that was known about Andrews's role of Karathen was that it was "an undersea creature that holds the key to Arthur Curry’s (Jason Momoa) quest to unite the Atlantean and surface worlds." On Tuesday, however, it became clear that Andrews would not be playing any old heroic fish swimming in the sea. To flesh out the role, critics turned to a set of descriptors that have likely hitherto never been attached to Andrews's name—at least until she signed on to playing "humongous," "Kraken-like ... villain," or "a Lovecraftian sea beast who lives at the Earth’s core," anyway. If you have any doubts that sweet, sweet Julie Andrews could possibly embody something so maleficent, well, it certainly helps that the film has matched her voice with something that looks like this:

Karathen, the sea creature voiced by Julie Andrews in Aquaman, 2018.

Before you get all riled up thinking that entering her eighties is enough cause for a living legend to be shunted to the side, let's be clear: it was in fact Andrews who would apparently sooner banish herself to the bottom of the sea then return to singing "A Spoonful of Sugar." In fact, Rob Marshall, who directed Mary Poppins Returns, even offered Andrews a role in the sequel—she simply "immediately" declined it. ("She said, 'This is Emily’s show and I want her to run with this. She should run with this. This is hers. I don’t want to be on top of that,'" he recalled at the film's premiere.)

And perhaps Andrews really did want Blunt to shine. Or perhaps she was offended by the rumor that she'd have played "the balloon lady," foreseeing that today's youth wouldn't remember that the role originally went to another legend, Angela Lansbury. We may never know the reason, but we do know one thing for sure: it's certainly easier to imagine Andrews capable of appearing in a box office competitor with the sole intent of shade after knowing what she looks like as a villainous kraken.

Related: Emily Blunt Is Absolute Magic in the New Mary Poppins Returns Trailer