'Eternals' star Kumail Nanjiani worked for months to nail down his epic Bollywood dance scene: 'It was so outside my comfort zone.'

• Kumail Nanjiani's Bollywood dance scene is a highlight of "Eternals."
• The star originally thought it would be a Bollywood action sequence.

One of the best moments in Marvel's "Eternals" comes nearly an hour into the film when Kumail Nanjiani's character, Kingo, performs a Bollywood dance sequence.

Nanjiani said the short scene for a fictional film within the film, was "the hardest thing" for him during production, especially since he was originally under the impression that it would be a totally different scene.

"When we first talked about the movie, [director Chloé Zhao] was like, 'There's a Bollywood dance sequence,' and I was like, 'Chloe, I don't think I can do that,'" Nanjiani said during the film's virtual press conference in October, which Insider attended. "She's like, 'OK, we'll make it a Bollywood action scene.'"

Nanjiani's relief was short-lived.

"Soon as I got to London, she's like, 'It's a dance sequence,'" Nanjiani said. "I was like, 'Get me a dance teacher right now.'"

Nanjiani said the film's choreographer, Nileeka Bose, worked with him "for months and months" on the scene, which incorporates tens of dancers. 50 people are listed in the film's credits as Bollywood dancers.

On "The Tonight Show" with Jimmy Fallon, Nanjiani said he trained for four months.

"It was so outside my comfort zone," said Nanjiani during the press conference. "Ultimately, for me, all that came down to trust."

"Just in meeting [Zhao], I was like, 'Oh, she's not going to let me suck in this thing,'" Nanjiani added. "So if she wants me to do something, I'm going to do it."

Ahead of the film's release, Marvel debuted part of the scene online, which you can watch below.