As new dark comedy series Bad Sisters arrives on Apple TV+, Danielle de Wolfe learns more from stars Sharon Horgan, Anne-Marie Duff and Claes Bang.

Five sisters, two life insurance investigators and a dead husband. It is a line-up that would not be complete without an open coffin - and an awkward case of angel lust.

These are the decidedly awkward foundations upon which Sharon Horgan's latest twisted comedy is built, a series which combines the Irish predilection for dark humour with decidedly sinister (and altogether more serious) undertones.

An adaptation of the original Flemish series Clan by Malin-Sarah Gozin, new Apple TV+ series Bad Sisters is written by, and stars, the Emmy-nominated and Bafta Award-winning Motherland and Catastrophe actress.

A complex dive into the unwavering bond of sisterhood, it is a gripping offering finely balanced by a host of contrasting personalities.

"The subject of sisters is something that's been explored really well in other shows, but here, the sheer number of the sisters and the connections between them, is what got to me," says Horgan, herself one of five siblings.

"And then these smaller groups within the five. Who looks after who? What's the relationship between the eldest and the youngest? How does the middle child feel? It's endlessly interesting to me."

Bonded at a young age by the untimely death of both parents in a freak accident, the Garvey quintet's connection is one they believe to be steadfast.

Except that all changes when one of the sisters, Grace (played by Anne-Marie Duff), finds herself increasingly estranged from her siblings as a result of her sociopathic husband John Paul Williams' coercive behaviour.

However, when John unexpectedly winds up dead, everything changes for the sisters.

With his widow grieving and the family coming to terms with the loss, John's life insurers arrive on the scene, launching a rather unorthodox investigation in a bid to uncover malicious intent.

"I love the passion of these sisters, how they would do anything for each other," says Horgan. "And, in fact, they do - they would kill for each other."

While eldest sister Eva (Horgan) remains the family's level-headed matriarch, we rewind the clock and witness her siblings' scheming over the group's annual Christmas dip at famed Dublin sea spot the Forty Foot.

What starts as a frustrated off-the-cuff quip about John's demise quickly gathers momentum, developing into what can only be described as a murderous plot.

After all, killing the root of the problem seems the only viable way to save their sister from increasing isolation.

"Quite often we're used to seeing these sorts of relationships in very gritty realism, so there is an element of this that is a sort of thriller-y caper," says Bafta nominee Duff, 51, best known for playing Fiona Gallagher in British sitcom Shameless.

"To have a very abusive relationship as the sort of spinal column of that story is clever, because it challenges the genre in a way, which is fun, but also heightens the stakes. It's not an art heist or a bank robbery. It's the rescuing of a woman. And so that's what makes it very sly and clever."

It is a series which also stars Brooklyn actor Eva Birthistle and Normal People's Sarah Greene as Garvey sisters Ursula and Bibi respectively, alongside Behind Their Eyes star Eve Hewson, daughter of U2 frontman Bono, as youngest sibling Becky.

Joined by Irish natives Brian Gleeson (Snow White And The Huntsman) and Daryl McCormack (Good Luck To You, Leo Grande) as the series' snooping insurance duo, this all-star cast is as impressive on screen as it reads on paper.

"For me, it was getting to play that guy and be so horrible. It's just a weird, perverse joy. But thankfully, I think other actors [feel] the same - you like being the prick," smiles co-star Claes Bang, 55.

"Who wants to be a hero?" interjects Duff, nudging the air beside her co-star. "Everybody knows what the hero's going to do - nobody knows what the prick's going to do."

Playing formidable liar and soon-to-be-dead misogynist John as part of the series, The Northman star says that in spite of his character's malicious behaviour, the underlying "spark" that remains between his character and Grace underpins their relationship.

It is a view clearly shared by co-star Duff. Expanding on Bang's comment, she notes the way in which, with no malice intended, many onlookers might find themselves asking why does she put up with it? Why doesn't she just walk away?

"But of course, there are so many elements that bind us. They can be to do with someone being very powerful, but also to deal with your own shame [or] of recognising the fact that you could be allowing someone to treat you that way, because acknowledging that also is acknowledging a failure - and being judged by the outside."

It is an altogether darker side to this sharp-witted comedy, with coercion being a subject Duff has come across previously as part of her research into the dark world of domestic abuse.

Having starred alongside actress Tessa Peake-Jones in Do You See Her, a short film by Women's Aid highlighting violence against older women, she says she was all too familiar with the central subject that weaves itself through Bad Sisters.

"I had been in touch with Women's Aid before and also have been to refuges where women live; some of them had been in very physically abusive relationships, but others had been in fantastically coercive ones," notes Duff.

"Love doesn't always look a certain way, sadly. Love can be fantastically complicated and ugly and unkind. And I suppose for us, our goal was to create that flame of love.

"In his own warped way, [John] really loves her and wouldn't be so terrified of losing her if he didn't.

"So if we could create that, if the audience could buy that and go, 'Well, that's a given', then everything else is the satellite."

Bad Sisters premieres on Apple TV+ on Friday.