“God gave John Paul the strength to be an unforgettable human being,” muses a stalwart Irish priest at the vindictive man’s funeral. Meanwhile, his doting wife looks on as her four sisters fret that somebody will discover the misdeeds that led to man’s death. Seems they all played a part in it — or did they?

Welcome to Bad Sisters, the wickedly fun, new dark comedy-thriller launching on Apple TV+ (Aug. 19). From Emmy nominee and BAFTA Award winner Sharon Horgan (Catastrophe, Pulling), the series is bound to become one of the season’s must-watch shows. Clever, inventive, and downright refreshing, Horgan — creator-executive producer-writer-star — takes viewers into the tight-knit world of the Garvey sisters, who've always had each other’s backs. When brother-in-law John Paul (Claes Bang delivering a believable foe) winds up dead, his life insurers launch an investigation to prove malicious intent. Well, the sisters must protect grieving sibling Grace (Anne-Marie Duff—a joy to watch in every frame). But when the insurers set their sights on the sisters, all of whom had ample reason to kill John Paul, suddenly everybody’s biting their fingernails.

“When Apple TV+ asked me what show I wanted to do next, they showed me this Belgian series, Clan, by Malin-Sarah Gozin, and said I think this is what you should do,” Horgan said. “I've never adapted anything before. I'd never written a thriller or an hour-long show—I'm used to half-hour sitcoms in my writing. But I just loved it. I found the premise hilarious and immediately got excited by what I could do with it. What would be my version be of this series? What if you set it in Ireland? What if you raise the stakes?”

So ‘Bad,’ So Good: Why Bad Sisters Works

Bottom line: This is one the best shows to hit a streaming series in some time and the all-star cast is wonderfully in sync. Unlike, say, The Morning Show, which tends to wander off with its creative shenanigans, Hogan grounds her characters in reality, even while mayhem swirls around. In addition to Horgan (as sister Eva) and Duff (Sex Education, Shameless, Nowhere Boy), this TV sisterhood is rounded out by Eva Birthistle (The Last Kingdom, The Bisexual), Sarah Greene (Frank of Ireland, Normal People, Dublin Murders), and Eve Hewson (Behind Her Eyes, The Knick). Brian Gleeson (Frank of Ireland, Peaky Blinders) and Daryl McCormack (a delight in Good Luck to You, Leo Grande) play two brothers/insurance investigators.

The storytelling here is wildly inventive, too. Viewers roll back and forth through time to witness the events that led to John Paul’s death — the guy is a racist, sexist, selfish, and sociopath, and the sisters believe their lives, and more importantly, Grace’s life would be better off without him. A few drunken jokes about offing the man, and suddenly things get real.

“I love dialogue and I usually start off with way too much of it — I could have two characters talking to each other on the page for way too long,” reflected Horgan. “What I love is to dive into a ‘world.’ It's a bit of an escape to create characters and give them the personality traits you wished you had — make them braver or quicker or somebody with more emotional depth or any of those things. And then, just like puppets, you just set them to work. I love trying to create real dialogue between real people. That's the thing, even in something is heightened like this [show]: if it doesn't feel like you believe it could happen, or if you don't believe that those words would come out of anyone's mouth, then I'm kind of not interested.

“Making something believable and authentic is a big part of what I enjoy doing,” she added.

As the series rolls through its 10 dynamic episodes, tensions build and potential romances form — we’re looking at you Eve Hewson and Daryl McCormack, who have stellar on-screen chemistry. We’re also given a unique character — Dublin itself.

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Location, Location, Location: Why Dublin Matters

Bad Sisters Sharon Horgan
Apple TV+

The series was filmed in numerous locales around Ireland, allowing audiences to experience parts of the country they may not have seen before in such detail on screen. Some of these include Malahide Marina and the village of Howth, both on the outskirts of Dublin, and northern areas like Ballintoy and Greencastle.

The real-life locale that plays the biggest role in the series is the Forty Foot. The epic swimming area in Dublin Bay rests nearly eight miles south of the city. The Forty Foot stands out here because of its deep water and unusual rock formations. Curiously, only men were allowed to swim there — signage still exists from this “gentlemen’s bathing place" — but feminist protests of the 1970s, changed things. The scenic location happens to be part of long-held tradition for many Dubliners known as the “Christmas Day swim.” It’s the place where the Garvey sisters in the series vowed to each other that no matter what happens to them in life, that Christmas dip at the Forty Foot happens.

Horgan, who’s never set her shows in Ireland until now, was inspired by the beauty of the area, using it to create the mood and feel of Bad Sisters. “I love the locale and all the characters,” she said. “My hope is that the series really gets under people’s skin. I want them to enjoy the thriller element of it, especially as it goes on because it gets pretty brutal. And you know, there's an incredibly abusive, dangerous relationship at the heart of this. And that [kind of relationship between Grace and John Paul] isn't just something that happens in other countries or miles away. It's literally your next your next-door neighbors."

“I really want people to see that and feel it and… just jump on for the ride.”

Bad Sisters premieres with two episodes exclusively on Apple TV+ on Friday, Aug. 19, followed by weekly episodes.