Here's how the new All Creatures Great and Small builds on the original books and TV series

Is All Creatures Great and Small based on a true story?

Yes! The drama is adapted from the books by veterinary surgeon Alf Wight, who wrote his novels-cum-memoirs under the pen name "James Herriot". This TV adaptation closely follows the James Herriot books – but with some dramatic liberties.

The real Alf (who died in 1995 aged 78) was raised in Scotland, graduated from Glasgow Veterinary College in 1939, and then moved to the Yorkshire Dales for a job working with local vet Donald Sinclair (renamed Siegfried Farnon in the books). He married local woman Joan (known to readers as Helen), and they had two children called Rosie and Jim.

Later in his career, Alf wrote a series of books about his work, his animal patients, and their owners. He began with If Only They Could Talk (1970) and went on to write a total of eight books.

The books in the "All Creatures Great and Small" collection include It Shouldn't Happen to a Vet (1972), Let Sleeping Vets Lie (1973), Vet in Harness (1974), Vets Might Fly (1976), Vet in a Spin (1977) The Lord God Made Them All (1981) and Every Living Thing (1992). (For confused American fans, in the USA they were published in omnibus format and given different names.)

And fans will be relieved to hear that Alf's family is firmly on board with this Channel 5 drama.

Nick Ralph, who plays James Herriot in the drama, told press: "We met Rosie and Jim, Alf White's son and daughter, before at the read-through. So, really early on in the whole process. And they were just lovely – they were really excited, really passionate about the new series, and really engaging and had some wonderful stories."

Callum Woodhouse, who plays Tristan Farnon, added: "Jim – he wrote a book about his dad, and he brought each and every one of us a copy and had bookmarked at every point in the book where our character pops up, and had written a little blurb in the front detailing his experience with that character. So he brought a copy of his book but it was individual to each one of us cast members. That was just such an amazing gesture."

What are the previous TV and film adaptations?

The first adaptation of the James Herriot books was a movie which came out in 1975, starring Simon Ward and Anthony Hopkins. They actually also made a sequel which was released the following year, but neither Ward nor Hopkins returned to their roles; it was not a big hit. (And for those wondering, it is now almost impossible to track down a copy of either film.)

However, in 1978 the BBC began airing a TV series based on the books – and this version was a huge success, ultimately running to seven seasons and a total of 90 episodes. The TV series starred Christopher Timothy, Robert Hardy, Peter Davison, and Carol Drinkwater.

The BBC's original All Creatures Great and Small started a weekly re-run on BBC Four on Thursday 4 February 2021 and is available to watch on iPlayer (but is not on Netflix, BritBox, or Amazon Prime). It can also be bought on DVD.

Finally, in 2011, the BBC made a three-part prequel called Young James Herriott. It starred Iain De Caestecker and was not re-commissioned.

Anticipating comparisons with the much-loved original BBC series, executive producer Colin Callender said: "I think this show lives comfortably and respectfully side by side with the original, but I have every conviction that the moment people start watching... they will immediately get absorbed and embrace this wonderful new cast. With [director] Brian Percival gloriously at the helm, I think that within minutes they will be caught up in this new show and fall in love with everybody."

What is different about this Channel 5 remake?

The team behind this new adaptation was keen to capture the feeling of the original books. Watching the series, "you're just swept away into a wonderful nostalgic bucolic world with wonderful characters whose mission in life is to do good, support each other, be part of a community," Channel 5 boss Ben Frow said.

However, there has been one significant change: the roles of housekeeper Mrs Hall (Anna Madeley) and James's love interest Helen Alderson (Rachel Shenton) have been greatly expanded.

"One of the ambitions of this production was that the women in the storytelling should be centre-stage and fully developed," Colin Callender said.

Shenton said: "From the books I learned about Helen through James and through his interactions and his feelings towards her, so what's really nice about our adaptation is we get to see Helen on her own and she's away from James and we know about her background, what she enjoys, what she doesn't, and she's a person all on her own before she meets him. So I guess that was the biggest difference.

"And I think what's really nice about getting to tell this story in front of a modern audience is, we get to show these women exactly as they were, which was well-rounded, tough, resilient, multi-faceted women." The actress was delighted to learn that the real Helen was the first woman in the village to wear trousers; she also heard from Rosie and Jim about "her wicked sense of humour and mischief."

As for Mrs Hall the housekeeper, Anna Madeley said she's a "slightly warmer figure" than in the books – and she also gets to be a character in her own right.

Praising screenwriter Ben Vanstone, she explained: "Ben's made her a really fully formed character and given her a really interesting backstory that she comes to the piece with, and I think from the get-go you meet a woman who is heart and soul of the house, and who is helping steer the ship, who is fully engaged and loves this surrogate family that she's nurturing.

"And so while her role is quite traditional, I think it is a fully realised and psychologically really nuanced - she can see what everybody needs, she's emotionally very courageous, and she's very principled and valued, but I don't think she's forgotten what it's like to be young and fall in love and make a mess."

How does All Creatures build on the books?

The creative team went back to the James Herriot books, where they found a story that's still relevant to modern Britain – and characters who we'll still love today.

Colin Callender said: "I started from the standpoint of, as i do with almost any show that I produce, which is: what would I like to see as an audience member? And I felt that what I wanted as a viewer myself and what I felt that the audience wanted was a show that we could all watch together, that could somehow reaffirm the basic values that inform Britain at its best, community, care of others, family, all those great things which I think we've sort of lost along the way.

"Those are the core values that are right at the centre of the books, All Creatures Great and Small, and as I began to think about it I also felt that the modern technology, the shooting technology the cameras, the equipment, would allow us to actually bring this world to life in a really glorious way that hadn't been seen before on camera. One of the starring characters of the show is the Yorkshire Dales, and with the new camera technology and drones and so on and so forth, I felt that we would be able to bring that to life in a way that was inherent to and part of the storytelling.

"And the other thing was that I felt that in the books there was a humour and a wit that was really rich and could be featured – and that the characters themselves in the books, there's a depth to these characters that I think that a contemporary audience wants, a contemporary audience expects now out of its dramas, that the characters are rooted in a psychological reality and a time and place. Because this was England after World War One, and between the wars, the depression, it is in the late '30s, and so this story seemed to be resonant with a whole range of themes that were strikingly relevant to today."

Director Brian Percival added: "My main influence rather was to go back to the original books and to look at it in a different way, look at it in a modern way, and far more sophisticated. We've all become more sophisticated in terms of the way that we tell a story, and the way we relate to it, and what those audience expectations are.

"But it was just about going to that with completely fresh eyes, and to look at it in today's terms, and with today's values, and not to try and copy or replicate anything but to give it a take of what I felt about it, what I felt about the characters, the landscape particularly, and how I wanted to tell that story."

He also found himself referring frequently back to the books. "There's a reference book there so that we can always look into that finer detail should we ever need it," he said. "Should we ever sort of think, 'I wonder what such and such a character would have done with that?' And there's probably 20 pages on it. And it's a great foundation and a great basis to then base a new vision upon."

All Creatures Great and Small started on Tuesday 1st September 2020 at 9pm on Channel 5 in the UK.

All Creatures Great and Small airs on Sundays at 9/8c on PBS Masterpiece in the US.

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