What's the story?

Saving The Greatest Horse.

Black Beauty? Red Rum? Silver?

Nope. Try again.

Champion? Seabiscuit? Valegro?

No. I'm talking about Scotland's famed workhorse: the Clydesdale. A new documentary highlights the plight of these giant beasts as they face what is being dubbed a "vortex of extinction".

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Tell me more.

The horses originated in the Clyde Valley, Lanarkshire, during the 18th century. Bred for heavy farm and industrial work, they were much in demand all over the world, with the most sought-after the pure blacks.

Back then, thousands of Clydesdales could be found around the Clyde Valley. Now, they're all but gone. Janice Kirkpatrick, an award-winning graphic designer based in Ayrshire who fell in love with horses at a young age, is on a quest to save the Clydesdale in Scotland.

What does that entail?

Research in tandem with a genetic expert has revealed that the small number of Clydesdales in Scotland is causing inbreeding issues, which could eventually endanger their existence.

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A remarkable journey follows, one that takes Kirkpatrick from the Clyde Valley and the Merryton farm where the horses were developed, to the Canadian Prairies as she traces a family who have protected the pure Clydesdale bloodlines for five generations.

When can I watch?

Clydesdale: Saving The Greatest Horse, BBC Scotland, Wednesday, 7.30pm.