A young associate of Rolf, the first Duke of Normandy, a Viking named Agnar, inadvertently allows himself to be drawn into the Land of Alf. He forgot that he could not accept the hospitality of the Alves, nor their food and drink, nor the love of their women. Too late he realized that he would not return to his native time. Having escaped from a magical land, the Viking finds himself in the world of the ancient Celts, many centuries before the birth of Christ. Here, under the yoke of local laws and traditions, he will have to make his own way. How long will even the strongest of the Druids be able to keep the freedom-loving northerner captive?..