Luna has been homeschooled ever since she was six, and all the friends she's ever needed have been in her books. But one day, her parents send her to regular school. Luna is nervous at first, but she warms up to the idea and is eager to make lots of friends! Only things don't go exactly as she imagined. Nobody seems to be able to see Luna, except for a girl in her class named Lily. Lily and Luna work together to figure out why nobody can see Luna. They piece together a truth that could bring Luna's world crashing down.