Ax misses his home. Now that he sees how desperate the Yeerks situation on Earth is, he wants to go home and get help from his fellow Andalites - and also let his parents know about the death of his brother, Prince Elfangor. Marco and the other Animorphs set out to help him, but end up trapped by the Yeerks instead. Now the're last on the giang Yeerk Pool ship, and Marco is about to have the nastiest surprise of his life: The mother he thought was dead is alive - and under the control of Yeerks named Visser One. Now Marco really has a reason to stay in the fight.