After the Animorphs' latest mission goes disastrously wrong, Cassie's finds herself alone, on a plane, heading who knows where and with Visser Three hot on her tail.The Yeerks have her trapped, thirty-three-thou feet in the air, with no escape and no Jake, Rachel, Marco, Ax or Tobias to save her.

How will she ever defeat the Visser without the help of her friends-and how on earth can she find her way back home.?