'Don't believe anything,' says Nicole Kidman of twisty HBO thriller 'The Undoing' with Hugh Grant

HBO's "The Undoing" is another dark, binge-worthy thriller from David E. Kelley, the creator of "Big Little Lies." But for fans of a certain marmalade-eating bear, it's also a link to the "Paddington" universe.

The show's stars, Nicole Kidman and Hugh Grant, played Paddington's fiendishly funny foes in the 2015 film and its 2018 sequel, respectively, making "Undoing" a sort of villain team-up.

"In some ways, 'The Undoing' is really the 'Paddington' origin story: how those two people became who they were," Grant jokes.

"God! Don't write that!" Kidman says with a laugh. Her daughters Sunday Rose, 12, and Faith Margaret, 9, "were absolutely mortified that I was playing the person that wanted to hurt the bear. I remember they didn't want to show their friends because they were embarrassed that I was the villain."

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The villains are much harder to spot in "Undoing" (premiering Sunday, 9 EDT/PDT), a six-episode limited series based on Jean Hanff Korelitz's 2014 novel "You Should Have Known."

The series follows Grace Fraser (Kidman), a successful therapist and wife to Jonathan (Grant), a pediatric oncologist, living in New York's Upper East Side. Their teenage son, Henry (Noah Jupe), attends a prestigious prep school, which suddenly becomes the eye of a media hurricane when a young mother (Matilda De Angelis) is brutally murdered the night after a glamorous school fundraiser. Jonathan vanishes the same day, making him a leading suspect in the case.

To say much more would spoil the drama's relentless, nail-biting twists, as Grace uncovers incriminating secrets about Jonathan and questions whether he's guilty.

"It was interesting to play somebody who cannot decipher her own life properly," Kidman says. "So many people say, 'I'm fantastic at reading everything, but when it comes to my own life, forget it.'"

With its rich housewives, intense therapy scenes and central murder mystery, "Undoing" has strong parallels to "Big Little Lies," for which Kidman won a best actress Emmy in 2017. She acknowledges "some similarities" between the soapy HBO dramas, but says the new show is more of a psychological thriller.

"It is meant to be a ride, and it's been particularly constructed so that each episode ends in a (cliffhanger)," says Kidman, 53, who also executive produces and sings the series' title theme. Her advice for watching: "Don't believe anything you get told. Nothing is what it seems."

The Oscar winner has been good friends with Grant since the early '90s, and even came close to a small role in his 2003 rom-com "Love Actually."

"But I feel like we've worked together many times," she says. "I've always felt strangely relaxed around him, which made it relatively easy playing husband and wife."

"They're both very compelling and very sexy together," adds director Susanne Bier (Netflix's "Bird Box"). "There was a fun, flirtatious (dynamic), and yet in these scenes, there are huge tensions between them."

Grant, 60, was drawn to the show's Hitchcockian elements: "well-dressed people in nice apartments, and something evil's going on." With Jonathan, "I liked the sense of, can this be for real? He's too wonderful, this man. Is there something we're not seeing? Then the layers of the onion come off quite fast in subsequent episodes."

"Undoing" is the latest project produced by Kidman's Blossom Films, which she founded in 2010. Blossom is now filming Hulu's "Nine Perfect Strangers," an adaptation of Liane Moriarty's 2018 novel that also stars Kidman and is co-created by Kelley. The series was set to shoot in Los Angeles before the coronavirus pandemic, forcing the actress to relocate production to her native Australia.

"I would like to be able to say it's easy, but it's actually difficult," Kidman says of shooting under COVID safety guidelines. "We get tested three times a week, everyone's masked, there's zones that you work in. It was so good to be able to give people jobs and to be able to do something right now. And I will only say 'for now,' because you can get shut down at any time. If there's a case, that's it. So it's very, very different."

Grant, meanwhile, is still in lockdown in London with his family, where his version of work is quite different.

"I've developed new skills, and I'm quite a good hairdresser now," he deadpans. "I started with my daughter's Barbie dolls. Then, having chopped all their hair to pieces, I ran out of dolls and went on to my children."

This article originally appeared on USA TODAY: Nicole Kidman, Hugh Grant talk 'The Undoing' HBO, 'Paddington' reunion