Bad Sisters’ Anne-Marie Duff Breaks Down Ian’s Bombshell News (Exclusive)

Warning: This post contains spoilers for Bad sisters season 2.

Anne-Marie Duff can’t help but mourn her misfortune Bad sisters character – even in death.

Since Duff’s character Grace was killed off at the end of the second episode of Season 2, her four sisters Eva (Sharon Horgan), Bibi (Sarah Greene), Ursula (Eva Birthistle) and Becka (Eve Hewson) have slowly unraveled the circumstances surrounding her sudden death, and the most heartbreaking revelation came in episode 7 when the true identity of Grace’s husband Ian (Owen McDonnell) was exposed.

“It was a sad twist in a way for me because I was like, ‘Oh, Grace, not again,'” Duff, 54, tells PEOPLE of her reaction to the revelation that Ian is actually an impostor who has been playing Grace. and her sisters. “She’s unable to move on. We need a good therapist—we need all those things.”

“That he’s ultimately a disappointment is so sad,” she adds of Ian draining Grace’s daughter Blánaid’s bank account after Eva gave him access and fled, leaving the Garvey sisters at a total loss.

Horgan tells PEOPLE that Ian being a con artist was really the “first idea” for the season, as she reveals, “He always wanted to be a bad guy.”

That Ian was a fraud wasn’t the only reveal so far though, as he and Eva also became romantically involved in episode 5.

“It came out of the writer’s room and we loved it,” says Horgan, 54. “I mean, we knew we wanted Eva to (she) try to move on, just try to turn her life around. She is menopausal. She was always drinking too much, sort of trying to fix herself.”

She continues: “But then the thing is, when something happens to you as traumatic as losing your sister, you’re so vulnerable and open yourself up that suddenly we thought, ‘Oh my God, what if she’s so open and vulnerable , that she lets him in?'”

Duff says it’s a “very interesting” dynamic that emerges between her character’s sister and husband because “you want (Eva) to have joy,” but there are so many layers to it.

“In season one, you have this weird parallel with the rape of Eva and the abuse of Grace, and then in season two, their lives are so strangely intertwined, right? In terms of the men in Grace’s life.” says Duff. “It’s very clever and strange.”

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Season 2 finale of Bad sisters premieres Wednesday, December 25 on Apple TV+.