Will The Undoing Get a Season 2? Creators of Hit Series Say It's Possible — but Not Probable

Now that we know who killed Elena Alves, will there be more installments of The Undoing?

The HBO thriller aired its sixth and final episode on Sunday, shocking fans by revealing the killer behind the murder at the center of the show. Though the show's stars and creators have said The Undoing is a limited series with a finite lifespan, director Susanne Bier did tease that the door is always open for a potential renewal.

"Of course you wonder what comes after this is over. We did joke about it on set. I won't rule it out, but it's not in the concrete works," Bier, who also directed 2018's Bird Box, told OprahMag.com of the likelihood of a sequel season.

Based on the 2014 novel You Should Have Known by Jean Hanff Korelitz, The Undoing stars Nicole Kidman as Grace Fraser, a Manhattan therapist whose life crumbles when her husband Jonathan (Hugh Grant) becomes the primary suspect in the brutal bludgeoning of another mom at their son's school.

It was adapted for television by Big Little Lies screenwriter David E. Kelley — who notably helped usher that other Nicole Kidman HBO show beyond a miniseries framework into a season 2 (and possibly a third entry soon).

Discussing the changes he made while taking the story from book to screen, Kelley told The New York Times that if they do a second season, they could explore more areas of the novel.

"For me, it started with loving [the book] and then going, 'What if this could be translated to the screen?'" he said. "For The Undoing, I kept wondering, 'What if the character of Jonathan came back?' That question started haunting me, and that was my springboard for an adaptation where we do deviate from the book."

"Susanne Bier and I both loved the part of the book where Grace was rebuilding herself after her world fell apart. But for the purposes of this run, it was more about the thriller aspect," he continued. "Who knows? If we did the extended life of Grace Fraser beyond this season of The Undoing, maybe we’d get into that reconstruction part."

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Bier recently told Entertainment Weekly that a season 2 of the series is not probable but still possible. "This is a tight story, which is why I think six hours is perfect," she said. "There's something about six that has a natural arc."

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"It's not like a drama series where you're not quite sure how they're going to evolve and you have a next season," Kidman, 53, also told EW. "That's why I say it's like cinema, because you have a beginning, middle and end."

"The thing about a limited series is it's so difficult because you're writing a much longer form of cinema that you have to keep people engaged in, and in some ways that's so much harder," she added. "That, as an actor, is delicious."

The Undoing is streaming on HBO Max.