Paul explores the River Oykel in Sutherland from its source in Assynt to the Dornoch Firth and the sea. He learns about the loneliest and highest war grave in Scotland, tries for trout in a lochan over 1,000ft above sea level and then hears tell of the riotous events of the Year of the Sheep. Downstream, he discovers the legacy of the Duke's giant toothpick when, in the 19th century, the fabulously wealthy Duke of Sutherland spent a fortune trying to create agricultural land out of a peat bog. In a remote glen, Paul meets a man who controversially hopes one day to bring back wild wolves to the Highlands. Journey's end is on the Dornoch Firth, where Paul learns about an ambitious project to recreate a huge native oyster bed.