During a brawl in their Gallic village, the magic potion that gives the heroes ASTERIX and OBELIX their superhuman power tips over. Before the druid Getafix can make another brew, the Romans capture him and catapult him into space from their galley at the edge of the word. They believe the earth is flat. Asterix and Obelix set out after Getafix. They end up in America, where Indians, who already hold Getafix prisoner, capture Asterix. The medicine man has designs on their magic potion and Getafix has to use every trick in the book to protect its secret formula. The three Gauls finally escape from the Indians and on their return home find their village burned to the ground and its inhabitants abducted. Our heroes free their friends, tear the Roman camp apart and send Caesar on his merry way.