The 'Late Late Show' host had his heart set on taking over the actor's role.
On Thursday's episode of The Late Late Show With James Corden, Aladdin stars Mena Massoud, Naomi Scott and Smith stop by to perform a crosswalk musical version of their film. While Massoud and Scott easily landed the chance to reprise their roles -- Aladdin and Jasmine, respectively -- Smith, who showed up unexpectedly to the show, had some competition for the part of Genie.
"What are you doing here? You don't need to be here!" Corden, who's covered in blue paint and outfitted in the Genie character's full costume exclaimed when Smith made his entrance.
"I'm the Genie, man. It's, like, you can't do Aladdin without the Genie, baby!" Smith said. "... I'm the Genie in the movie, man. Come on. It's obvious."
"... You may be Aladdin on the silver screen, but this is live theater," Corden reasoned, before Smith declared, "Challenge accepted."
Despite his protests against letting Smith take the Genie role, Smith pushes him to play the monkey, Abu, assuring the host that he "could rock" the role.
"I'm not playing a monkey. I'm not playing a monkey! I don't care what you say. I don't care if you say it's me. I'll shut the whole thing down! I'm not in a million years playing a monkey!" Corden yells before cameras hilariously flash to him in full monkey costume.
The group starts the show by singing "Friend Like Me," after which Massoud and Scott praise both Smith and Corden's performances.
"That was amazing. Will is just phenomenal," Massoud gushed. "He's the Genie. I mean, come on."
"James makes a pretty cute monkey as well," Scott added.
Next up for the group was "Prince Ali," a song that seemed to be Corden's tipping point as he rushed off to pout after the number.
"It's just everyone's saying, 'Will's great.' I haven't got any lines," Corden told Smith. "You're all having so much fun out there."
"You're comparing yourself to me? I'm a multiple Academy Award nominee, man," Smith answered, much to Corden's dismay.
Smith changed course, instead pointing out everything Corden has in common to the monkey.
"You are Abu. You're charming. Abu is charming. You're mischievous. Abu is mischievous," Smith reasoned. "You're both, like, really handsome little devils. You know what I mean?"
After that pep talk -- and as soon as Smith handed Corden a banana -- all was well, as the group performed their last number, "A Whole New World."
When ET's Kevin Frazier caught up with Smith at a London screening of the film, he said he came to love his role.
"I was feeling sexy about myself as the Genie," Smith said with a laugh. "I felt sexy about myself."
"... This movie has a lot of really great ideas that I love and the concept of Genie, somebody whose whole existence is dedicated to helping people find themselves and create the lives that they want, that aspect is almost the purest definition of love," he added. "So for me playing Genie -- you're always looking for something that you can connect to with a character that's authentic -- that devotion and dedication is what I aspire to with my life."
Aladdin is in theaters now.
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