Michelle Yeoh Admits She'd Never Seen “Wicked” Musical Before Joining Movie Adaptation: 'Had No Clue'

Oscar winner Yeoh plays Madam Morrible in the adaptation of the long-running Broadway show

Before Michelle Yeoh joined the cast of Wicked, she was certainly no die-hard Ozian.

In fact, the 62-year-old Oscar winner knew very little about the musical when director John M. Chu, who previously worked with her on Crazy Rich Asians, approached her about playing a key role in his adaptation of the Broadway musical.

“I at that point had no clue what he was talking about because I had not seen Wicked the musical before,” she told The Hollywood Reporter at the Nov. 9 premiere in L.A.

“I knew Wizard of Oz, who doesn’t, but not Wicked, because I hadn’t been going to the theaters and not doing what I love which is watching musicals, for quite a while I hate to say,” she continued.

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The prequel to The Wizard of Oz serves as an origin story for The Wicked Witch of the West, when she was a misunderstood university student, Elphaba Thropp, with green skin and special powers. Chu wanted Yeoh to play Elphaba’s mentor and Shiz University headmistress, Madam Morrible. Cynthia Erivo stars as Elphaba, while Ariana Grande plays her roommate-turned-friend, Glinda (the future Good Witch).

Yeoh said she read the script before calling back Chu to discuss it. “[I] said, ‘This is a musical and she sings.’ And he said, ‘Oh easy, you’ll have fun, you’re up for the challenge. And then the next thing I knew I get this video call and it was him with Ariana and Cynthia saying, ‘It’s imperative you come and join us now.'”

But Yeoh said the idea of singing put her on edge. “I was terrified, I was not just nervous.”

The Everything Everywhere All at Once star previously told PEOPLE she's not a natural vocalist. “I love singing. But normally it’s in the shower, not when there’s other people around,” she quipped.

Working with a vocal coach gave her confidence. “She made it so much fun, I was hitting notes that I never thought that I would try,” Yeoh said.

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Erivo also helped put lingering nerves at ease. “Most of my singing parts are with Cynthia. She said, ‘Just sing it out, girl. I can hear you singing. Just come out with it.’ So they made me so comfortable,” said Yeoh. “It’s not that I’m going to have my own concert, but at least I had a lot of fun, and that was nice.”

Wicked is in theaters nationwide on Friday, Nov. 22.

Buy PEOPLE’s Wicked special edition here.