Owain is starving and feverish because of his wound. He and Dog eventually find refuge with a farming couple in the Welsh marches, who nurse Owain back to health. Once recovered he sets out again for Viroconium, but finds it abandoned and already beginning to fall into ruin. He lives there alone for some time, supporting himself by hunting, until he meets a young beggar girl, Regina, who is also hiding amid the ruins, and they join forces.
A band of British marauders captures Regina but Owain rescues her and they start off southwards, with a vague plan of getting across to Gaul. On the journey Regina becomes gravely ill with pneumonia. The pair are forced to ask for help from a Saxon family. They have no need of a new thrall (slave) but a Saxon who is spending the night at the farm says he will pay a gold piece for them to look after Regina if Owain agrees to come with him as his thrall.
So Owain goes south with his new master, not knowing whether Regina will live or die. For the next eleven years he lives with the Saxons, eventually gaining his freedom and fighting in a war between Saxon kingdoms. After many adventures he leaves the farmstead of his former master, who by this time is dead, and sets off on a quest to find Regina.
The book works well both as a story about Owain and his growth to manhood and as a portrayal of the changing relation between the Saxons and the British, who are now established in Wales. The writing is vivid and Sutcliff has a fine ear for dialogue. It is always difficult in historical novels set in a remote period to find the right balance between modern vernacular and fustian, but Sutcliff's touch is sure and this makes it easy to believe in the characters.