The narrative of the poem concerns the struggle between King James V and the powerful clan Douglas. The King has banished the entire family from his realm, including James of Douglas, the Earl of Bothwell, who had been his protector during his youth. The Earl and his daughter Ellen take refuge with Roderick Dhu in his castle on an island in Loch Katrine. At the beginning of the poem a mysterious knight calling himself James Fitz-James arrives at the castle and is granted hospitality. During his brief stay, he falls in love with Ellen but finds rivals for her affections in Roderick himself and in Malcolm Graeme, a young knight loyal to the King but moved by sympathy at the plight of Douglases.