The Android

When Marco runs into his old friend Erek he doesn't think too much of it. He's got more important things to do, like helping to save the world. But then Marco finds out Erek's been hanging with some of the kids at the Sharing, and he starts to think that something just a little weird is going on.So Marco, Jake, and Ax decide to morph and check old Erek out. Just to see if he's been infested with a Yeerk. The good news is that Erek's not a human-Controller. The bad news is that Erek's not even human.
K.A. APPLEGATE is the author of the bestselling Animorphs series, as well as the Remnants and Everworld series, Home of the Brave, and the Roscoe Riley Rules series. She lives in Tiburon, California.