Kidman, who plays abused housewife Celeste Wright on the new HBO series, stripped down to her birthday suit for a shocking nude shower scene.
The episode exposed more than just the bruises her character suffered at the hands of violent husband Perry, played by Alexander Skarsgård — the pair flashed plenty of flesh during a racy sex session!
"Keith must be going nuts with jealousy watching his wife expose her naked body to another actor — and the world!" tattled a Hollywood snitch.
"He's in showbiz, too, so he knows there's things you have to do sometimes — but it can't be easy for him."
As Radar has reported, tensions have been growing between Kidman, 49, and her hubby, especially after Urban, 49, was seen getting cozy with his former opening-act, then 21-year-old singer Kelsea Ballerini.
It's all clearly taking a toll on Kidman, who has appeared recently looking sickly thin!
But she hasn't shied away from showing off her wilting body on camera. Earlier in the series, she bared her breasts while doing a striptease for her fictional hubby, who also talked her into performing a solo sex act on a webcam!
"Big Little Lies" centers on the relationships of several California women who have young children, and has been called "a multilayered tale of friendship and painful secrets." The show also stars Reese Witherspoon, Laura Dern, Shailene Woodley and Zoë Kravitz.
Sources claimed that while Kidman's acting naughty on the screen, in reality, all she wants is to have another baby — but Urban has nixed the idea. The couple, married since 2006, have daughters Sunday, 8, and Faith, 6.
"I still have the faintest hope that something may happen to me this year," Kidman said recently of her desire to add to their family. "My grandmother gave birth to my mother at 49. I would be happy beyond happy and just welcome it with open arms." Do you think Nicole looks hot or not? Should Keith be worried? Let us know in the comments!
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