The year is 50 B.C. Caesar is hungry for new conquests. At the head of his glorious legions he decides to invade the island that lies at the very edge of the known world, that mysterious land known as Britain. Victory is swift and total. Or - almost. One single tiny village manages to resist, but its forces are growing weaker so Corddlia, Queen of the Britons, decides to send her most faithful officer Jolitorax to seek aid in Gaul, in another small village famed for its dogged resistance to the Romans. At the village in question, Astérix and Obélix already have their hands full. Their chief has entrusted them with the task of making a man of Goudurix, his young pain in the ass nephew recently arrived from Lutèce. And their task is far from accomplished. When Jolitorax arrives to ask for help, the Gauls decide to give him a barrel of their famous magic potion. Astérix and Obélix will accompany him back to Britain - as will Goudurix. After all, the voyage seems to offer an excellent opportunity for completing the young man's education. Unfortunately, nothing ever goes quite to plan.