Jolan has agreed to leave his family and serve Manthor, who saved Thorgal's life. The mysterious mage has promised Jolan an exceptional destiny—if, that is, the young man proves worthy of it. So begins a series of trials during which Jolan, on his own at first, will meet four other youngsters. They, too, have unusual powers. And they, too, are on their way to Manthor's castle. Will they be allies, or enemies?