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

The Harry Potter alum, 66, was a fan of season 1 of Bad sisters when it premiered two years ago, and she tells PEOPLE that a less-than-a-minute pitch from creator and star Sharon Horgan and director Dearbhla Walsh was enough to get 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 haven’t regretted it for a second.”

“I was really happy to participate,” Shaw added. “I mean, season one was just breathtaking.”

Shaw says she “didn’t know how they were going to handle season 2” after the first season ended and all the questions surrounding JP’s (Claes Bang) death were revealed: Grace (Anne-Marie Duff) had enlisted the help of her neighbor Roger (Michael Smiley) to put her husband on a four-wheeler and make his death look like an accident instead of 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 the murder of JP, whom she has long called ‘The Prick “, as at that point they had been making valiant attempts to kill him for months.

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

Shaw, who joins as Angelica, Roger’s nosy sister who bonds with Grace, teases that Horgan will “take things to the extreme” in season 2, just as she did in the first episode.

“She thinks of the most impossible and somehow swims through it through her writing,” Shaw says. “It’s very clever.”

She continues, “Sharon writes for that group, so the girls’ humor is kind of incorporated into it, and all the eccentricities that came with that—I think we all put into it—then became part of the writing because Sharon was the writing is. 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 air on Wednesdays.