Unknown
Having learned that someone has discovered proof of alien life and hidden the proof on the top-secret base called Zone 91, Cassie and the Animorphs struggle to keep the evil Yeerks away from the place.
Having learned that someone has discovered proof of alien life and hidden the proof on the top-secret base called Zone 91, Cassie and the Animorphs struggle to keep the evil Yeerks away from the place.