Shape-Shifter

In the fifth book of this middle grade sci-fi series, a teen abducted by aliens becomes a shape shifter, unrecognizable to everyone, even himself.
 
For nine months, Todd Aldridge was missing. Stories swirled about him throughout his hometown of Metier, Wisconsin. Was he kidnapped? Abducted by aliens? The kids at his junior high school were keen on the alien story. Metier is a UFO hotspot, after a...