Why a second season of The Undoing is unlikely
With only one episode left to answer every last question, there's already talk about whether the limited series will continue after its first season. After all, HBO has been known to extend popular limited series past their original plan. But for The Undoing, it's seems unlikely. "This is a tight story, which is why I think six hours is perfect," says director Susanne Bier of choosing the episode number for the series. "There's something about six that has a natural arc."
Knowing it was a limited series changed how Kidman approached the project to begin with. "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 told EW at the start of the drama. "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. That, as an actor, is delicious."
That's not to say that the show couldn't return, but it is to say that the initial approach to the story was a six-episode limited series and nothing more.