Renée Zellweger is earning rave reviews and generating Oscar buzz for going over the rainbow as Judy Garland in Judy.

But just how did she manage to inhabit one of the most legendary entertainers of all time — without letting the weight of that get her down? By mostly ignoring that aspect of Garland’s life, Zellweger says.

“I tried not to think too much about the obvious, which is how adored Judy is and has been through generations, and how she’s an icon for the ages,” Zellweger told EW while visiting the EW and PEOPLE video suite at the Toronto International Film Festival. “I tried to take that off the table and look at it as an exploration of trying to understand the human experience on the other side of that stardom. I think otherwise I would’ve just run away.”

It’s not just audiences who are heralding Zellweger’s performance; costar Finn Wittrock, who portrays Garland’s fifth husband, Mickey Deans, was also mesmerized by her work. “I feel like I was with Judy for most of this shoot, and then when we were done it was like, ‘Oh right, that’s what you look like,’” he said.

Another resource that helped both performers was immersing themselves in footage and recordings of Garland. “YouTube has become this amazing acting reference. I’m not doing an ad for YouTube, but it is incredible because you can find hidden gems,” Wittrock said. “I did find this — they started to make this documentary of following Judy behind the scenes, and [Deans] shows up in it… falling in love with her and being there for the highs and lows. Most of my job was to watch old Judy Garland movies and to fall in love with her, so that wasn’t too hard.”

Zellweger added that Garland’s music was constantly playing on set, keeping them bathed in the sound of her voice. And for her, Judy provided an opportunity to delve into the life of someone she had a personal passion for. “It was just an exploration that was propelled by curiosity and adoration, really,” Zellweger said.

Watch the video above for more. Judy opens Sept. 27.

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Judy (2019 movie)
Renee Zellweger goes over the rainbow in Judy Garland biopic Judy
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