The story takes place just before the 1715 Jacobite Rising, with much of Scotland in turmoil. Frank Osbaldistone, the narrator, quarrels with his father and is sent to stay with an uncle, Sir Hildebrand Osbaldistone, in Northumberland. Frank falls in love with Diana Vernon, Sir Hildebrand's niece, whose father has been forced to go into hiding because of his Jacobite sympathies. Frank's cousin, Rashleigh, steals important documents vital to the honour and economic solvency of Frank's father, William, and Frank pursues Rashleigh to Scotland. Several times his path crosses the mysterious and powerful figure Rob Roy MacGregor, known as Rob Roy, an associate of Sir Hildebrand.