Belonging! That would be nice. Olivia's guardian days are over. Turns out, not sneaking out at night to fight monsters has left her isolated. As the magic turning her to stone gets terrifyingly worse, she grapples with strained friendships and family tensions. Yip and Glori struggle with their own problems, and Hector is trying his best to keep them all from falling apart. A baby brother brings light and hope to Olivia's heart but a disastrous thirteenth birthday brings her world crashing down. She believes someone has swapped her brother with a changeling. Her parents think she is jealous of the new baby. They are wrong, and Olivia will do anything to get him back, even if it means losing herself, and giving in to the darkness growing inside her. Entering the lands of the fae is more dangerous than any of them could imagine.