Movies Watch the Super Mario Bros. Movie cast trick Jack Black into wearing a Bowser costume Kelly Clarkson is at it again. By Nick Romano Nick Romano Nick is an entertainment journalist based in New York, NY. If you like pugs and the occasional blurry photo of an action figure, follow him on Twitter @NickARomano. EW's editorial guidelines Published on March 2, 2023 11:42AM EST Jack Black is doing the most on his press tour for The Super Mario Bros. Movie — even when he's doing it unintentionally after being pranked by his castmates. The School of Rock and Jumanji star was notably absent from the couch of The Kelly Clarkson Show when stars Chris Pratt, Charlie Day, and Keegan-Michael Key walked onto the set. So host Kelly Clarkson went looking for him… and found him backstage in a Bowser costume. "I'm not going out there," Black said. "'Cause everybody said we were gonna get dressed in costumes, and I'm the only stupid guy that got dressed in a costume, and I'm not going out there now." Clarkson coaxed him into it by letting Black walk through the VIP stage entrance before Black changed his tune rather quick for the cameras. To be honest, it all feels very staged and not really like a "prank." But then again, it is Black. He actually might have thought his castmates were as wild as him. Black voices Bowser in The Super Mario Bros. Movie, which also features Pratt as Mario, Day as Luigi, and Key as Toad. The cast also includes Seth Rogen's Donkey Kong, Anya Taylor-Joy's Princess Peach, Fred Armisen's Cranky Kong, Kevin Michael Richardson's Kamek, and Sebastian Maniscalco's Spike. Jack Black in costume. Weiss Eubanks/NBCUniversal When the first trailer for the animated film came out in October, Black was being himself, joking in a video message to fans, "Look at all this Koopa muscle I packed on. And this flowing mane doesn't just appear overnight." Given this latest stunt, the rest of the press tour leading up to the movie's premiere on April 7 should be very interesting. Want more movie news? Sign up for Entertainment Weekly's free newsletter to get the latest trailers, celebrity interviews, film reviews, and more. Related content: Mamma mia! The Super Mario Bros. Movie trailer reveals Seth Rogen's Donkey Kong, Anya Taylor-Joy's Peach It's-a me! Chris Pratt debuts his Super Mario voice in trailer for animated movie John Leguizamo, OG cinematic Luigi, says new Super Mario Bros. movie casting 'kinda sucks' Close