Renée Zellweger can’t believe how destitute Judy Garland became toward the end of her life.

“I was very surprised and found this shocking that someone who had worked since she was 2 years old, on that level, could find herself in financial dire straits at that stage in her career,” says Zellweger.

The Oscar-winner portrays the “Wizard of Oz” star during the last months of her life in the biopic “Judy,” director Rupert Goold’s adaptation of the stage play “End of the Rainbow.”

“The consequences of some decisions that were made for her early in life,” Zellweger says on this week’s episode of “The Big Ticket,” Variety and iHeart’s movie podcast. “It surprised me how naive people were about the consequences of medication in a child’s body and what that can do. Naïve in that we didn’t know or ignorant rather — that’s a better word. Ignorant is a better word.”

Following the world premiere of “Judy” at the Telluride Film Festival, there was instantly an outpouring of predictions that Zellweger would return to the Oscar race for her transformative work. Through makeup, wigs, fake teeth and on-the-nose recreations of Garland’s wardrobe, Zellweger is Judy Garland. She was so committed to recreating Garland’s hunched posture that she ended up at a chiropractor “a few times” while shooting the movie in London.

Like Garland, Zellweger spent years being hounded by paparazzi and the tabloid press. But then in 2010, Zellweger decided she need a break. She stopped working in Hollywood and started working on herself, which included seeing a therapist. Is it any wonder that Garland’s life resonated with Zellweger?

“I understand the schedule and I understand the choices have to make,” she said. “I understand public scrutiny and I understand having a public persona where some people might feel that they know you and that’s really lovely and a blessing in so many ways. And then there’s a lot of misunderstanding and misconception in the mix and I understand that, too. Projection, and you know, false narratives.”

Having first showed off her vocal chops in 2002’s Chicago, Zellweger returns to singing on screen, performing many of Garland’s classics. She also duets with Sam Smith on “Get Happy” on the “Judy” soundtrack.

“Isn’t that ridiculous?” Zellweger said, adding, “It took him like two minutes…He’s so gifted. What a special, sweet, fun person. He just sparkles. He just came in and he was like, ‘Here we go!’”

You can listen to the entire interview of Zellweger on this week’s “The Big Ticket” below. You can also find it at iHeart or wherever you listen to your favorite podcasts.