When nine-year-old Rob Cole, child of poor 11th-century English farmers, loses his mother, he is consigned to the care of a barber-surgeon who takes him around the countryside, teaching him to juggle, sell potions of questionable value, and assist him in basic medical care that ranges from good practical first-aid to useless ritual.  When, eight years later, his mentor dies, Rob takes the wagon, horse, and trappings and embarks on a life-changing journey across Europe to learn real medicine from Avicenna in Persia.  Through a Jewish physician practicing in England, he has learned that Avicenna’s school is the only place to learn real medicine and develop the gift he has come to recognize in himself.  In addition to skill, he discovers in encounters with patients that he has sharp and accurate intuitions about their conditions, but little learning to enable him to heal them.  The journey with a caravan of Jewish merchants involves many trials, including arduous efforts to learn Persian and pass himself off as a Jew, since Christians are treated with hostility in the Muslim lands he is about to enter.  Refused at first at Avicenna’s school, he finally receives help from the Shah and becomes a star student.  His medical education culminates in travel as far as India, and illegal ventures into the body as he dissects the dead under cover of darkness.  Ultimately he marries the daughter of a Scottish merchant he had met but parted with in his outgoing journey, and, fleeing the dangers of war, returns with her and their two sons to the British Isles, where he sets up practice in Scotland.