King Arthur has disappeared and Kaamelott is ruled by the tyrannic Lancelot. A crook finds by luck a trace of Arthur who lives anonymously as a slave in Hispany. He catches him with the will to sell him back to Kaamelott. But the ancient king is freed by his friend the duke of Aquitaine. Despite his will, he is getting back to Kaamelott and made leader of the rebellion to overthrow Lancelot and his fellows, all inepts.