It shouldn’t happen to a veteran television concept … but it does. Amid the current, insatiable vogue for safely bankable nostalgia in all facets of entertainment – Hollywood’s unstoppable quest to remake every reasonably popular movie in history is a cash juggernaut laying waste to originality and innovation – no small-screen classic of yesteryear is safe from a reboot, a reimagining, or a restart.

Sometimes, such wistful TARDIS trips to the past are immediately successful. Rock & Chips, featuring the exploits of a young Del Trotter and his mates, was funnier than it had any right to be, while Endeavour – ITV1’s forthcoming Inspector Morse prequel set during the curmudgeonly copper’s days as a fledgling DC returning to Oxford – is truer to the spirit of the parent series than its descendant spinoff, Lewis, and highly enjoyable to boot.

However, on other occasions, these journeys through TV’s back pages take a little longer to strike the right note.

Young James Herriot, featuring Iain de Caestecker (The Fades) in the title role, has plenty going for it and yet it’s difficult to shake off the sense that somebody flicked through an old copy of the Radio Times and stuck their finger onto a page at random to decide what the next remake du jour was going to be.

Yes, All Creatures Great and Small (a BBC flagship of the ‘70s and ‘80s, with Christopher Timothy as a country vet in between-the-wars Yorkshire) was a huge success in its day. But is there any mileage in rewinding even further, to Herriot’s days at Veterinary College?

Swapping the rustic charms of the Dales for grim, grey Glaswegian backstreets, this three-part serial also dispenses with a lot of the gentle humour of the earlier series for something a little grittier. The youthful James Herriot is a spirited, socially awkward character whose wide-eyed enthusiasm makes him prone to cock-ups – misdiagnosis could be his middle name – and whose zealousness sets him on a collision course with stuffy college professors and locals alike.

He’s also horrendously green, suffering several times at the japing hands of new ‘friend’ Rob McAloon (Ben Lloyd-Hughes), a laconic, languid blade with a love of gambling, drinking, joking and not doing any work – the eternal student archetype.

‘He’s been here for five years,’ the wonderfully-named Whirly Tyson (not a vacuum cleaner) remarks of McAloon, ‘and he’s still a pig.’ ‘I can see what you mean,’ Herriot mutters, but it turns out Whirly – played by Amy Manson (Being Human); a progressive feminist struggling for equality in the chauvinist veterinarian college by campaigning for a ladies’ loo to be installed – simply means that their classmate is still technically only a second year.

Somehow, this unlikely threesome become best pals within a few minutes, spending most of their free time in the local pub and living together in digs owned by randy landlady Mrs Monro (the splendid Natasha Little), whose over-the-top flirtation brings some much-needed comedic relief to proceedings. ‘Darling man,’ she coos to an embarrassed Herriot one morning. ‘Delicious to see you … gin and tonic?’

Of course, it’s animals which take precedence in the young vet’s life, not suggestive widows, and the principal storyline of this opening episode is the curious case of an ailing dray-horse, its impatient owner and his compassionate son. It’s not exactly Crocodile Dundee, but it’s fairly entertaining nonetheless.

The cast is uniformly excellent; the oh-so-gloomy sets and the bleak exteriors look suitably timely, and there’s a moment of incongruous genius where Herriot has a moment of revelation and a light-bulb flares above his head. Yet whether there’s enough depth to the programme to carry it through three instalments without drifting into amiable inconsequentiality remains to be seen.

Young James Herriot could be a success; but then again, it could be a case of a resurrection too far. Sometimes, it’s better to let sleeping vets lie.

Airs at 9pm on Sunday 18th December 2011 on BBC One.

> Buy James Herriot’s book All Things Bright and Beautiful on Amazon.

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