Caesar has just submitted Hispania to Rome. At last almost, because a small village still resists the invader. He then captures the son of the village leader and sends him as a hostage to the Babaorum camp so that he receives a Roman education. But the Gauls recover the little boy and Asterix and Obelix take him back to his village in Hispania. On this long journey, they will have to fight against the Romans who want to recover the hostage and ... against the whims of the little boy!