Fiona Shaw Joins Bad Sisters Season 2 After She Was Told The Plot In ’25 Seconds’ (Exclusive)

It didn’t take much to convince Fiona Shaw to join the gang of the Garvey sisters.

The Harry Potter alum, 66, was a fan of Season 1 of the Bad sisters when it premiered two years ago, and she tells PEOPLE that a less than one-minute pitch from creator and star Sharon Horgan and director Dearbhla Walsh was all it took to bring her on board for Season 2.

“Sharon and Dearbhla told me the plot in 25 seconds over breakfast one morning and I kind of followed it, but whatever it was, I wanted to be part of that team,” says Shaw. “And I didn’t regret it for a second.”

“I was happy to be involved,” adds Shaw. “I mean, Season 1 was just breathtaking.”

Shaw says she “didn’t know how to go about Season 2” after the first season ended with all the questions surrounding JP’s (Claes Bang) death revealed: Grace (Anne-Marie Duff) had the help of her neighbor Roger (Michael Smiley) to put her husband on a four-wheeler and make his death look like an accident rather than the murder it had been.

It was a shock that Grace’s sisters, Eva (Horgan), Bibi (Sarah Greene), Ursula (Eva Birthistle) and Becka (Eve Hewson), were not actually involved in killing JP, whom they had long since dubbed “The Prick ,” as they had spent months at that point making valiant attempts to kill him.

Season 2 takes place two years after JP’s death, with Grace and the Garvey sisters moving on, but “as past truths resurface, the ladies are thrust back into the spotlight, suspicions are at an all-time high, lies are told, secrets are revealed, and the sisters are forced to find out who they can trust,” according to the official synopsis.

Shaw, who joins Angelica, Roger’s nosy sister, who forms a bond with Grace, teases that in season 2, Horgan will “take things right to the edge” just like she did in the first installment.

“She thinks about the most impossible, and then she swims herself out of it through the writing,” says Shaw. “That’s very smart.”

She continues, “Sharon writes for that group, so the girls’ wit is kind of infused into it, and all the eccentricities that came along—I think we all put into it—then became part of the writing because Sharon writes it all the time.”

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The first 2 episodes of Bad sisters season 2 is now streaming on Apple TV+. New episodes are broadcast on Wednesdays.