Paul explores the River Garry, which flows from the Grampian Mountains, restages the Battle of Killiecrankie and falls off a bridge before climbing the ‘speckled hill’.

Paul Murton explores the upper reaches of the river Spey, Scotland’s third longest river, and travels through Badenoch to a hidden love nest, before working up steam on a heritage railway.

Paul Murton explores the lower reaches of the Spey, famous for its forests, whisky distilleries and salmon as it flows north towards the coast. On the way Paul hears tales of loggers who floated timber down the river from the 17th century onwards. He also takes to the water in a canoe and discovers the rare and endangered freshwater mussels that were once harvested for their precious pearls, which adorn royal crowns.

Paul Murton discovers the source of the River Nith, high in a remote forestry plantation. Heading downstream, he hears the story of the Knockshinnoch mining disaster - how 116 men were saved from entombment after a massive earth collapse. He also learns about the first man to make a bicycle with pedals, heads to the riverside home of Robbie Burns and finds out how a Dumfries man helped Neil Armstrong walk on the moon.

Paul Murton follows the eastward course of the river South Esk from its source in the hills above Glen Clova to the Montrose Basin, and on to the sea. Along the way he searches for Scotland's rarest plant, goes electro-fishing to discover more about the ecology and general health of the whole river system, and rides a motorbike to the ancestral home of Harley-Davidson.

Cameras follow the River Ayr as it flows from Loch Glenbuck towards the sea and the Clyde coast. In the Ayr Gorge, Paul Murton encounters the tale of radical preacher Alexander Peden, whose life on the run forced him to hide in caves while still preaching hell-fire sermons to the people.