Bored by homework and bullied at school, twelve-year-old Gwyn Rae reluctantly takes on a Heritage Fair project to boost his history mark. He begins to investigate the papers of his ancestor, Daniel Rae, with help from his older sister, Maddie. Together they discover a notebook filled with writing only they can see and an iron key that seems to react to their touch. When the key unlocks a secret door in an old church, Gwyn and Maddie are launched into the adventure of their lives.