Aquaman Has Special Voice Cameo From Mary Poppins

The original Mary Poppins will be voicing a character in the upcoming Aquaman film. Julie Andrews will voice the undersea creature Karathen, an instrumental figure in the title character's quest to unite the undersea and surface worlds.

"We wanted the Karathen to have the voice of a classic British actress, albeit somewhat digitally altered," producer Peter Safran told EW. "And when we found out Julie was interested and available and excited to do it, casting her was a no-brainer."

Coincidentally, Aquaman is already prepared for a head-to-head box office competition with Mary Poppins Returns, a sequel to the role that Andrews made famous. Emily Blunt is starring in this new interpretation, and Andrews declined to appear in cameo. She has reportedly stated that she didn't want to distract from Blunt's interpretation of the character.

Andrews hasn't appeared on the big screen for years, but has starred in the Netflix series Julie's Greenroom and has voiced characters in movies like Shrek Forever After and Despicable Me 3.

Mary Poppins Returns opens on December 18. Aquaman will follow on December 21, though Amazon Prime members will have access to advanced screenings on December 15. For more on Aquaman, check out the dozens of things we learned from its director.