Julius Caesar is furious! Unable to suppress the rebellious Gauls, the morale of his troops is at rock bottom, and his opponents in the senate sneer at him. The head of the secret police, Primojverius, suggests that he send a spy disguised as a druid to the Gallic village. And sure enough, a Roman spy arrives at the Gauls just as the druid Panoramix runs out of one of the ingredients for the magic potion. Therefore, the virtuous Asterix and his friend Obelix embark on a long odyssey to Mesopotamia, where he will find the necessary ingredient. But beware: the crew is also accompanied by a malicious Roman spy!