Fifteen-year-old Octavia has always felt like she exists just outside everyone else’s world. Lonely, homeschooled, and never quite able to understand the rules everyone else seems to know, she finds comfort in the woods behind her home.

She uncovers a buried box containing an old journal and a tiny carved horse she doesn’t remember owning. Etched into the horse is a mysterious symbol, one connected to a message she wrote years ago: Treehouse when the veil is thin.

Octavia deciphers the message and follows the clue.

She finds herself in Otempra, a hidden realm where the friends she thought she had imagined are very real, and they have been waiting years for her return. But something is wrong. Travel between the realms has mysteriously stopped, strangers from Earth have settled in Otempra, and Octavia’s unexpected arrival makes her impossible to ignore.

For the first time in her life, Octavia has found a place where she feels like she belongs. Now she may be the only person who can protect it.