Animorphs - The Interrogation

The Animorphs are back on Earth and they have no idea why. They recall a presence known as The One and they know it has Ax. Otherwise, they have little to go on. To save Ax they must find out about this strange entity, but since Andalites havn't seen Kelbrid space for so long, there's only one person they know that may have info and he's currently in a maximum security cell in Kansas...