All Creatures Great and Small season 6 finale finally answers Tristan mystery

It wouldn't be an All Creatures Great and Small season finale if you weren't reaching for the Kleenex (other brands are available) – this time prompted by what happened with Tristan.

Following his return to Darrowby from the front line, he hadn't quite been himself, however hard he tried to convince those around him that all was just dandy. Mrs Hall was quick to pick up on it, while Siegfried — wrapped up in his own crisis, brought on by the beloved housekeeper's absence — remained oblivious.

But it all came to a head in the final episode of season 6, when Tristan's mask didn't so much slip as disintegrate entirely, as the horrors of what he'd witnessed were laid bare and his emotions rushed to the surface.

Just as he had on numerous other occasions since returning, Tristan accompanied his brother to examine a shire horse that was having a problem with one of its hooves. But the visit proved anything but routine.

Shortly after entering the stable, Tristan faltered. When Siegfried instructed him to "go to its head," he hesitated before slowly approaching the horse. After a few steps, he froze, a look of sheer terror spreading across his face, which had turned ghostly pale.

Tears welled in his eyes as Siegfried asked him once more to attend to the horse, unaware of what was happening to his brother. But Tristan's feet were rooted to the spot, and moments later he bolted from the stable, jumped into the car, and drove off.

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Ahead of season 6, Callum Woodhouse teased trouble for his character, discussing how Tristan spends the series "trying to push a lot of things down and make everyone think that he's absolutely fine".

"He's the usual Tristan that we all know and expect, but we're sort of drip-fed… that things aren't all OK," he added.

"There's stuff he's probably not fully talked about, not fully expressed yet, which he was masking throughout this series with drink and with jokes — which is obviously always Tristan's way — but I'm sure more of that will get unpacked over time."

And in the finale, we finally learned the extent of what he’d experienced — and why he had been awarded the Military Cross, something he hadn’t wanted to discuss when Siegfried and Mrs Hall first asked, excitedly.

During a heartfelt conversation with Siegfried in the church, where he'd been since the early hours, Tristan spoke of his friend Billy, with whom he'd been inseparable since training. They were moving camp when they came under fire.

"Suddenly there was this noise," he said, unable to fight back his tears.

Billy had been hit. "He was in a bad way."

"I didn't fully grasp what had happened, so I went to help him — and he screamed at me not to move an inch."

The whole field they were standing on was covered in land mines.

"Someone moved over there — another bang; someone here — another," he recalled, which is when the horse pulling their equipment began to panic.

"You weren't afraid of the horse. What you couldn't bear was his fear," noted Siegfried astutely of his brother's panic in the stable the previous day.

With no medic on the scene, Tristan did what he could to help, but he was unable to save his friend.

"There was a mine right next to me, and if Billy hadn't screamed, I would have been killed," he said.

"I got a medal because I managed to save a few chaps, but Billy wasn't one of them. He saved me, but I couldn't save him. The Cross should be his, not mine."

Tristan added that he had tried to push the thoughts out of his head, "but then you see something or you hear something," as was the case with the horse.

"No one wants it to be over more than me, but if all it takes is some scared horse to wrench me back, then maybe it never will — in here."

Tristan then thumped his chest before breaking down, as Siegfried held him.

In the aftermath of Japan’s surrender, the "last of Britain's enemies to be "laid low," a new dawn is heralded once again. But for Tristan, and the other fortunate ones who survived, a different kind of war has begun.

Coming to terms with Post-Traumatic Stress Disorder — a term that wouldn't be coined until 1980 — and learning to live with its daily demands, as we see with both Tristan and Tom, another Darrowby resident recently returned from front-line service, will be an ongoing battle that touches every part of their lives — and one that may have no end in sight.

All Creatures Great and Small seasons 1-6 are available to watch on 5. You can order James Herriot's All Creatures Great and Small from Amazon.

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