At eleven years old, Arthur Good has what is called acute Pareidolia, an amazing gift that lets him see the hidden things inside everyday objects. His gift has revealed a hidden world that coexists alongside this one, after Arthur answers a help wanted sign that only someone with his ability could have seen, the unusual job changes Arthur's life forever. Working at Hagedell Castle for Sir William Elden, he must try to remove a family curse, unfortunately, becoming involved in a centuries old feud with an immortal king. Helped by a new friend, Penny Black, a blind girl who has acute audio Pareidolia, they work together to solve the clues that will reveal the doorways into another world.