'The Under People. They live in a huge Cave. They are thought to be boring upwards. Giant worms and flying ants. Underground magic.' Mickle, the palace cat, knows something is wrong. He can feel it in his whiskers. Then he finds scribbled notes revealing that the kingdom in danger. (Yes, of course he can read. And speak - when he chooses to!) Mickle can't trust the King and Queen with his mission, so he approaches Prince Michael and together, with the wise old mare Minerva, they set out on a perilous search to find the sinister Under People before they can invade Astalon.