All Creatures Great and Small Christmas special delivers disappointing Tristan update

But sadly, actor Callum Woodhouse didn't feature in this year's festive episode (Thursday 21st December) – and it was also hinted that we probably won't see him for quite some time, given that Siegfried, who was clearly missing Tristan, has offered new vet student Richard Carmody his brother's old room.

"He shan't be using it for a while," he said.

The newcomer had grown on the patriarch of Skeldale House, but in typical Siegfried fashion he refused to admit anything of the sort.

"Because it's convenient," he added. "You can answer the night calls. But keep your hands off my whisky, especially the good stuff."

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It's unsurprising that Tristan isn't due back anytime soon, given that the Second World War hasn't yet reached the halfway point, but Woodhouse did share a photo on Instagram of his last day of filming, which was captioned, "Over and out for now," which indicates that we've not seen the last of him.

But it looks unlikely that he'll appear in the currently unconfirmed fifth season.

Speaking previously about the impact of Tristan's absence on the characters, Nicholas Ralph, who plays James, said: "We miss Tristan a lot.

"And James in particular, he's his best friend. He's his brother in the surrogate family, so he's hugely proud of him for becoming his own man, spreading his wings and getting out from underneath Siegfried's watchful eye."

And naturally, the cast also missed working alongside Woodhouse.

"The character James misses Tris, but also we missed Cal on set and hanging out," Ralph added. "He's a wonderful, wonderful actor."

Rachel Shenton, who stars as Helen, said: "He's still in the WhatsApp group sending pictures of the dogs [laughs]."

All Creatures Great and Small is available to watch on My5. If you're looking for something else to watch, visit our TV Guide or take a look at the rest of our Drama coverage.

You can order James Herriot's All Creatures Great and Small from Amazon.

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