The actress portrays Lucille Ball in the Aaron Sorkin film opposite Javier Bardem as Desi Arnaz. The movie, which debuts on Dec. 10, sees Kidman undergo a transformation to portray the comedy legend — a feat she says wouldn't have been possible without Urban, 54.
"He's just very supportive. He's in there going, 'I believe you can do it, go for it. What do we need to do to support you?' Which is a fantastic partner in life," Kidman, 54, told Extra while on the red carpet premiere of the film in New York City.
The two married in 2006, and share two daughters: Sunday Rose, 13, and Faith Margaret, 10. (Kidman also has two kids with ex-husband Tom Cruise, daughter Isabella and son Connor, now 28 and 26, respectively).
This Thanksgiving, Kidman shared a sweet photo of herself and Urban hugging while at the beach, with the actress writing on Instagram, "Just feeling incredibly grateful 🧡."
Earlier in the week, Kidman appeared on Live with Kelly and Ryan where where called Urban her "favorite person," alongside their two daughters.
Kidman also told host Kelly Ripa and Ryan Seacrest that she tried to back out of playing Ball after backlash following her casting.
"I went, 'What have I said yes to?' — to which I then went, 'Oh no, I'm not right. Everyone thinks I'm not right so I'm going to try to sidestep this,'" she said. "And the producer Todd Black and Aaron Sorkin were both like, 'Absolutely not.' I was in Australia and they were like, 'No.' And thank god, because then I was so grateful because I got to fall in love with her."
Being the Ricardos takes place during one week of filming the couple's famous sitcom I Love Lucy, during which Lucy and Desi "are threatened by shocking personal accusations, a political smear, and cultural taboos," per the film's official description. Lucy and Desi were married in 1940 and later split in 1960.
News of Kidman's casting brought on backlash from fans who thought other actresses should play the legendary actress in the Sorkin film.
Kidman previously said taking on the role of Ball was daunting because it was out of her "comfort zone," but added that she hoped she was funny as the famous comedian.
Courtesy Everett Collection; Amazon Prime Video/Youtube
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Despite her self-doubt, Kidman got the approval of Ball and Arnaz's daughter, Lucie Arnaz, who praised the actress as "spectacular" in the role.
"What she did was astounding," Lucie told Palm Springs Life. "She's got such poise and class."
Kidman told Extra the hardest part of portraying Ball was her learning mannerisms and voice.
"I had eyebrows put on and that was it," Kidman said, saying she studied Ball every day. "It was working with a dialect coach that was extraordinary, a movement coach that was extraordinary and then studying, studying, studying, and Aaron going, 'I'm not interested in all that. I just want you to be real.'"
She added, "A lot of it is studious then abandon… A very strange collision of needing to be very, very loose and needing to be very, very prepared."
Being the Ricardos debuts in theaters Dec. 10 and on Amazon Prime Video Dec. 21.