Set in the tenth century, when Vikings roamed and rampaged from Scandinavia to the Mediterranean. A boy abducted by the Vikings from his Danish home is made to take his place at the oars of their ships. Later, he is captured by the Moors in Spain and, escaping from captivity, washes up in Ireland, where he marvels at the Christian monks. Eventually, he contributes to the Viking defeat of the army of the king of England, and returns home a Christian and a very rich man.