Actress Renée Zellweger isn't afraid of a challenge. So when she signed up to play Hollywood star Judy Garland in a film about the icon, she dove into the research. "There's so much material out there," Renée, 49, says of the movies, concerts, and interviews she studied.

She thought about calling Judy's daughter Liza Minnelli for advice, but mostly she studied the star herself. "She's so comfortable," Renée says of watching the 1963-1964 The Judy Garland Show. "She's being herself. She was so funny and cool."

Judy is set in 1968 as the legend arrived in London to perform a series of concerts. "It's 30 years since she shot to global stardom in The Wizard of Oz," says producers, "and yet Judy is fragile… She is exhausted. Will she have the strength to go on?"

judy garland

Judy, who worked from the time she was two, died of an accidental overdose in 1969 at age 47. Renée understands the demands of Hollywood, too. After starring in Chicago, Cold Mountain, and two Bridget Jones movies, she needed a break. And in 2010, she stepped away from acting.

"I was taking inventory of my life," she says. "Work had begun to feel like an obligation… when [making movies] should have been exciting opportunites or life adventures." During her six years off, she fell in love with musician Doyle Bramhall, traveled, and studied screenwriting.

In 2016, she returned to star in Bridget Jones's Baby, proving she's funny and cool herself. Now Renée is energized to play Judy. "Renée is a massive fan," says her friend. "She admired Judy, her trailblazing, her raw talent."

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To get into character, Renée worked with vocal and acting coaches. "She's studying all of it," shares the pal. "She feels like she's transformed into Judy, body and soul." And if Renée is nervous about playing her idol, it's only because she wants to do Judy justice. "Her biggest challenge has been that she honors Judy's memory in the most respectful way," he pal tells Closer. "She's fully aware that this is a role of a lifetime."

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