The thing you should know is that everyone is in really big trouble. Yeah. Even you.

Jake's grandfather has died. It blows the family away -- especially Jake's mom. So Jake's parents decide they should all travel to the grandfather's home to help with any arrangements. In another state. For three or four days.

This is a very big problem for Jake's brother, Tom. He can't be away from the Yeerk pool for that long. So Tom refuses go -- and his father insists. But Tom's Yeerk will do anything to survive. Including making his father less of a problem.

Now Jake, the other Animorphs, and Ax have to find a way to protect his father without Tom discovering their secret. And without having to choose between his father's life. . . and Tom's.