Gradlon, a young Pict, is predestined to be the ruler of his clan. From early youth on, he undergoes an extraordinary initiation where he must face, among others, great deprivations, terrible pains, barbaric rituals and even the gods. Scathach the immortal, a witch of the Skye islands and mistress of the great warriors of Bretagne becomes his teacher. At the end of his training, he becomes a Berzerker, the ultimate warrior, devoid of all fear! The treason of his brother and of all his clan and the resulting revenge, will make him a legenderry hero, who will ultimately rule over Ys, the island-state.