Welcome to the Autumn Realm, the wealthiest of the seven magical realms of Faery, where a human girl called Mouse serves in the home of the High Lord. Drawn into a changeling bond when she was just a child, Mouse was spirited away to the Autumn Realm and raised by the Folk. A life among faeries is all she's ever known...
And then a blue moon rises on the eve the High Lord announces Mouse's changeling is returning to Faery and strange things begin to happen—a human is caught sneaking through the faerie gate, the Autumn Prince takes a sudden interest in her, a mysterious creature tries to kill her, and a nightmare begins haunting her sleep.
Something sinister is happening in the Autumn Realm and Mouse must do all she can to protect not only her life, but the life of her changeling.