All Creatures Great and Small's James confesses devastating tragedy to Helen

And he also took the opportunity to ask James about his health after the vet was ruled unfit to serve in the military due to contracting brucellosis, a bacterial disease which he might have contracted while treating Crabtree's infected herd last year.

"Still thanking your lucky stars, I'll bet," said the postie, to which James replied, "I''m grand, thank you," before moving the conversation swiftly on.

But Crabtree also shared the same sentiment.

"I reckon things turned out for the best, don't you?" he said, referencing both James's safe return and the fact that he can once again lend his expertise to treating animals like Rose.

"We're both lucky, in a way. I'm glad some good came of it."

But those comments didn't sit well with the vet, which Helen immediately picked up on.

While grabbing a drink at The Drovers, she encouraged him to confide in her, and after a pause, he spoke candidly.

"They both said I was lucky to have got brucellosis," he said.

"Well, you were, I suppose. Very!" she responded. "That one visit [to treat the infected herd] could have changed everything."

But he still wasn't convinced.

"Well, you were sent home before you finished your training," Helen continued. "That's fortunate in anyone's book."

But as James knows all too well, the training can be "as dangerous as the real thing".

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"It certainly felt that way when my crew were shot down," he uttered solemnly, which was news to his wife.

"You never said," responded Helen, who was taken aback by the tragic reveal.

"I didn't want to frighten you in case I flew again," he explained.

Helen took his hand in her own, encouraging him to open up further, but her husband claimed that he had "made his peace with it", although his demeanour didn't exactly inspire confidence.

"I'm so sorry, James," she added.

And it's not just James who has been profoundly impacted by what he experienced during his service.

Samuel West, who plays Siegfried, previously said that Tristan has "obviously changed" following his return from Cairo.

"And he's changed in ways that I don't fully understand," he expanded. "He's obviously seen some horrible things which he's not talking about. And he's obviously masking with drink and good humour.

"He can't have had as happy and as boozy and as joyful a time as he says he has."

All Creatures Great and Small seasons 1-4 are available to watch on My5. Season 5 is airing new episodes on Thursdays at 9pm on Channel 5 and My5. You can order James Herriot's All Creatures Great and Small from Amazon.

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