Sister Boniface Mysteries stars tease season 4: "When you think it couldn't get bigger, it does"

"Sam still has to manage his heart slightly throughout this series with Ruth returning yet again to confuse him, I think.

"There’s quite a few up and downs, actually, we have threats of losing the whole set-up with the force and our investigation team.

"There’s all of those lovely moments to play through, and yeah, really complex cases this year, lots of brilliant and kind of funny moments as Sister Boniface’s mind wanders off and explores the unexplorable for most people."

Series star Lorna Watson also revealed: "There’s some really lovely moments, actually, between Sister Boniface and Sam this year as well. We see the depth of their relationship, I think, which was lovely to shoot and lovely to show.

"Again, these standalone episodes where it really does feel like a whole new world. We have a tribute to the old Batman-style movies, we have a Generation Game-esque show, the convent is also under threat.

"There’s a lot of drama behind the scenes, aside from the cases that need to be solved."

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She added: "Tensions are high, I think the residents of Great Slaughter are brought together and you really feel that sense of unity, togetherness and camaraderie. I would say it’s quite big this series.

"I don’t think you’ll be disappointed. Max and I, we say this every year, but just when you think it couldn’t get any bigger, it does.

"I really feel like this is a big series with a lot going on and we had an absolute hoot shooting it. I really hope people enjoy it, it’s exciting."

Having first aired back in 2021 as a spin-off to Father Brown, Sister Boniface Mysteries has continued to go from strength to strength, and if the teasers are anything to go by, season 4 may be the biggest instalment yet.

The synopsis for the upcoming season reads: "Elsewhere in the series, a bucking bronco goes haywire on the set of a game show, a killer scarecrow stalks the streets of Great Slaughter, the Scottish invade, a femme fatale drops to her death in a stunt gone wrong, and to top it all, CC Lowsley (Robert Daws) has arranged something called 'team building'.

"Meanwhile, Reverend Mother Adrian (Carolyn Pickles) is keeping a secret, one that could tear the Sisters' lives apart as they know it…"

Sister Boniface Mysteries returns for its fourth season in 2025, which will air on UKTV's U&Drama and on BritBox International.

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