All Creatures' Nicholas Ralph and Rachel Shenton on baby Jimmy and the return of Tristan

All Creatures Great and Small is back for a fifth season which brings joy and turmoil for new parents Helen and James.

As Spring 1941 arrives, vet James ( Nicholas Ralph ) is away from home and serving in the RAF and he and his crew-mates are getting ready to embark on their first bombing mission.

Back in Darrowby, wife Helen ( Rachel Shenton ) is looking after their baby Jimmy, with help from housekeeper Mrs Hall (Anna Madeley). Meanwhile, head vet Siegfried ( Samuel West ) and his trainee Carmody ( James Anthony-Rose ) are struggling to keep up with their busy caseload in the absence of both James and Siegfried’s laid-back brother Tristan ( Callum Woodhouse ), who is serving with the Royal Army Veterinary Corps, but is due to return later this run.

What to Watch caught up with Nicholas Ralph and Rachel Shenton to chat about what’s in store in the fifth season of All Creatures Great and Small …

All Creatures Great and Small is back! Where do we find Helen and James?

Rachel Shenton: “Because James is at war, Helen’s navigating motherhood single-handedly, although she has support from the surrogate Skeldale family.”

Nicholas Ralph: “And James has done bomber training and is a few flights away from real missions. This is when they were putting recruits through the training process more quickly. And James takes a fatherly role and feels a responsibility and pressure to look after the younger recruits. But the odds aren’t in your favor on the bombers…”

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Did you do any research into what life was like in the RAF back then?

Nicholas Ralph: “I had to learn the RAF salute, and then teach it to our supporting artists! But I also went to RAF Hendon in North London, which has hangars full of planes starting from World War One right through to the modern day. It was great going back and seeing the Spitfires and Lancasters. I also went to the Churchill War Rooms, and the Imperial War Museum. And then when we filmed the scenes in Lincolnshire surrounded by all the supporting artists and the planes it was incredible and very exciting.”

What journey do James and Helen go on this time?

Rachel Shenton: “As Nick says, there's a probability James might not come home, and that’s unthinkable to Helen. But when he’s in Darrowby, she's having to teach him how to be a parent because he's been absent. There are difficult moments to navigate, but they do the right thing by each other. They communicate really well together, even if they get pulled in different directions. That's always lovely.”

Nicholas Ralph: “Yes, you always believe in them coming back together, they're always there for one another. And we see that again, they are a team. But experiencing the war affects James. And there are challenges because he’s missing so much and when he sees Jimmy, he thinks he’ll take looking after a baby in his stride. We'll see how that works out!”

Have you enjoyed working with the babies playing Jimmy?

Nicholas Ralph: “They’re sweet and their faces light up when they recognise you! In one scene, I think Helen had gone picking berries, but the baby kept grabbing them, so there were about 30 berries in the pram, he was half baby, half berry! But we also had a ‘concrete baby’…”

Rachel Shenton: “That’s the [dummy] ‘jelly baby’ for rehearsals, which feels like a stone, it’s heavy! I like the focus a real baby brings to set, everyone's nicer. And filming the christening was lovely, the baby behaved impeccably and remembered what he was doing more than anyone else! But one of the biggest jobs we had was to stop the baby's attention going to the boom mic, because it’s like a big furry animal above our heads!”

And how are things with Helen and her sister Jenny (Imogen Clawson) and dad Richard (Tony Pitts)?

Rachel Shenton: “A land girl arrives from the city and Jenny's eyes are opened. Jenny's a young woman with her own mind now and it’s hard for Helen to let go. But Helen also reconnects with their farm, gets her wellies back on and goes on a journey back to herself.”

Tristan (Callum Woodhouse) returns from the front later in the run after being absent for series four. Has it been lovely welcoming Callum back?!

Nicholas Ralph: “It’s brilliant! The show missed Tristan, and we missed Callum. It’s been a boost to the show and everybody on set. James and Tristan have a wonderful relationship, so we have fun scenes.”

Rachel Shenton: “Yes, Callum was back for a day, and then it was like, ‘I forgot you haven't been here!’ He slotted back in so nicely.”

James helps a cow give birth near the RAF base in the opening episode, what other animals appear this time?

Nicholas Ralph: “With the cow, it mirrors the very first episode when he saved his job by birthing a calf. It's a reminder of what he does best. We also had a whiffy ferret, a smart collie, and a poodle who walked on its hind legs! And we have Hamish [a whippet/greyhound/lurcher cross taken in by trainee vet Carmody, played by James Anthony-Rose] who can wave, I couldn’t believe it!”

Rachel Shenton: “And Hamish also talks on cue! He's amazing!"

And is Tricki Woo, the pampered pooch of Mrs Pumphrey (Patricia Hodge) returning?

Nicholas Ralph: “Yes, even though Derek, who played Tricki, has retired, which is a shame, we've got lovely Dora. She’s more excitable and not as cool, calm and collected as Derek, but she’s wonderful!”

Finally, what do you both still love about working together on the show?

Rachel Shenton: “What happens after five years is that I know all Nick's jokes. They were hilarious for the first two seasons, not so much now!”

Nicholas Ralph: “Still hilarious if you ask me! Even more so now I think!”

Rachel Shenton: “No, it's lovely. We spend so much time together and that can only help with what we're trying to portray. It sounds cheesy, but we're all really excited when we get to work together again and hang out, it’s good fun!

Nicholas Ralph: “It's been half a decade. But what an absolute treat it's been. We've definitely got a shorthand and inside jokes, maybe sometimes to the annoyance of people around us!"

All Creatures Great and Small returns in the UK on Thursday, September 19 at 9 pm on Channel 5 and will also be available on streaming service My5. It will air in the US on PBS Masterpiece early next year.