Momoa, who has played half-human, half-Atlantean hero Arthur Curry since 2015, posted his excitement on Instagram with a picture of him and Kravitz.
“I’m so proud of u zozo bear (sic),” the caption read. “On and off screen OHANA. DC WB ohana Lola and Wolfies big sister is CAT WOMAN😍😍😍 Unbelievable so freaking stoked. Your going to have so much fun Aloha P bear.”
Kravitz is the daughter of musician Lenny Kravitz and actress Lisa Bonet, who has been married to Momoa since 2017 but together since 2005.
Kravitz voiced the character of Catwoman in the animated film The Lego Batman Movie and has previously appeared as the Marvel Comics character Angel Salvadore in X-Men: First Class.
The actor currently stars in the Fantastic Beasts franchise as Leta Lestrange and the HBO drama series Big Little Lies as Bonnie.
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According to reports, she screen-tested with Robert Pattinson, who plays Batman in Matt Reeves’ new film. and won the role over the likes of Zazie Beetz, Alicia Vikander, Ana de Armas, Ella Balinska, and Eiza González.
Kravitz is the third black woman to play the live-action character after Eartha Kitt and Halle Berry.
Anne Hathaway was the last actor to play Selina Kyle in a live-action film after appearing in 2012’s The Dark Knight Rises.
Jeffrey Wright has been cast as Commissioner Gordon while Jonah Hill is reportedly playing an unnamed villain in the new adaptation, believed to be inspired by the Batman: The Long Halloween comic run from Jeph Loeb.
Set after the events of Batman: Year One, the story follows Batman's early days of crime-fighting as he tries to foil a mysterious killer named Holiday, who murders people on holidays, one each month.
Jay & Silent Bob Reboot director Kevin Smith said he heard this news from a “good source” on his Fatman Beyond Podcast.
The Batman is scheduled to hit cinemas from June 25, 2021