The story of fifteen year-old Bobby Phillips begins on an ordinary school day when he awakens to go to school. The ordinary-ness of it ends abruptly when, as he's in the bathroom getting ready for the day, Bobby looks into the mirror and sees... Nothing! Bobby has woken up invisible, and he doesn't know how he got that way or what to do to become normal again. Things get more urgent when people start "looking" for Bobby and wondering where he is. One of the best parts of this book is the friendship Bobby strikes up with Alicia-- a blind girl he meets in the library. The best thing about Alicia is that she can't "see" that Bobby is invisible, and she is one of the only people treating Bobby as if he's a normal person. 
 I loved the twist in this that brings in the science-- explaining how a phenomena such as this might actually happen. This book has mystery, unanswered questions, and great characterization. It's really easy to love Bobby and Alicia. This one's a winner!