The Illusion (Animorphs #33)
By K. A. Applegate.
Description
The Yeerks possess a weapon that could be the biggest threat to the Animorphs yet. The anti-morphing ray transforms a person in a morph back to natural form. Unless they find and destroy the top-secret ray, the Animorphs could be expose for good. - from Amzon
ISBN(s)
0439070333, 9780439070331