The spectators of the book realm

In the ancient Book Realm, the Spectators are an ancient human race entrusted by the Elder Council with magical keys that open the doors to other book realms. Mariana carries a council-given key to a brutal war-torn fantasy realm, where she witnesses its greatest historical conflict without altering events. Inside any book realm, Spectators are invisible, intangible, and unable to affect the people or events they observe.