In season 7 of All Creatures Great and Small, Granville Bennett, a small-animal specialist (played by Caolan McCarthy), arrives on the scene and in turn, encroaches on Skeldale House's territory.

As per the official synopsis: "James is excited about new developments in veterinary medicine, but a new vet in the area threatens the status quo."

"Our big introduction to Granville is in the pub," said newcomer Caolan McCarthy, who described his character as the "life and soul of the party".

"He's parked his sports car outside and the three vets come in looking for him. He's there looking very urbane in his modern, three-piece suit, surrounded by locals, mid-story.

"The immediate reaction is: who is this guy? Where has he come from?"

But while Bennett is a "fresh and unique presence" in the tight-knit community, he "ingratiates himself with the locals very quickly".

"So that creates a bit of suspicion, I would say, from the off, with the three Skeldale vets," he added.

Discussing the show's latest addition, Samuel West said Granville's arrival "really messes them up".

"Suddenly Siegfried is ordering new treatments which they don't necessarily need and almost certainly can't afford. He starts working everyone all the time, throws open the practice to all comers and gets rid of the idea of appointments, all because Siegfried thinks he’s falling behind him."

Yet, first impressions can be misleading.

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"In Siegfried's mind, this alpha male vet who is quietly brilliant probably never has days off and is impossible to compete with," he said. "[But] Granville turns out to be quite relaxed about the whole thing and, on his day off, he goes swimming.

"The Granville Bennett of Siegfried's imagination is much bigger, more dangerous and very different from the one he actually gets to know" – and there even comes a point when "Granville actually needs his help.... [which] puts him back into a place of honest appreciation of where he is".

Callum Woodhouse, who plays Tristan, personally enjoyed Granville's impact on the show, describing him as "an amazing addition".

"His presence shakes up Siegfried and James, particularly because of his apparent level of success, wealth and attitude to his work and life in general," he added.

"But of course, a lot of mutual ground is found and their relationship grows over the course of the episodes."

The latest instalment picks up in 1946, with the war behind them and "Skeldale House once again full – and livelier than ever – as familiar faces reunite under one roof and look ahead to a hopeful new chapter".

The series description continues: "The world at large may be changing, but inside this slice of Yorkshire, the Dales will always offer the same perfect escapism. Packed with warmth, humour and community spirit, the series brings more heartwarming tales of people and animals alike."

A host of familiar faces return to Darrowby, including Nicholas Ralph as James Herriot, Samuel West as Siegfried Farnon, Anna Madeley as Mrs Hall, Rachel Shenton as Helen Herriot and Callum Woodhouse as Tristan Farnon.

Also reprising their roles are Patricia Hodge as Mrs Pumphrey, alongside her cherished Pekingese Tricki, Tony Pitts as Helen's father Richard and Imogen Clawson as her sister Jenny.

Maimie McCoy also returns as Mrs Hall's friend Dorothy, who is dating Siegfried, alongside Mollie Winnard as barmaid Maggie and Gaia Wise as "society beauty" and Tristan's girlfriend, Charlotte.

Caolan McCarthy joins the cast as vet Granville Bennett, with more guest stars appearing across each episode.

All Creatures Great and Small season 7 releases on 17 September at 9pm on 5. Seasons 1-6 are available to stream now on 5.

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