But when water begins stalking Nick around high school, it awakens a latent synesthesia and applies scents to the colors of a magic he didn't know he had. Cindy, a weaver of fire, knows more, but not enough to prepare them for the appearance of a living, talking door.

They will cross this threshold to find answers to their parents' murder, what their gifts mean, and what plans a magical serial killer has for the world. With the help of a feisty sylph and a sentient door, they just might make it, but only if they can survive the angry nixies, bloodthirsty redcaps, bone-crushing trow, and the friendship of a fairy queen who may not want them to succeed.