The Learmonths have survived eight centuries by guarding their secrets. Now someone inside the family is giving them away. The Vigilia Noctis knows too much. It knows about the Learmonths, about the creatures that have lived hidden among humans for centuries, and most dangerously, it has discovered a secret connected to the Queen of Elfland that was never meant to leave Thomas Learmonth’s keeping. Charlotte thought learning the truth about Thomas the Rhymer would answer the questions that brought her into the Learmonths’ world. Instead, it has placed her at the center of an old war. To discover what the Vigil wants, she must convince its members that her loyalty to the Learmonths is beginning to fracture. Rane knows the deception could work. He also knows what will happen if Charlotte is discovered. As Thomas searches centuries of memory for the moment his family was compromised, old betrayals begin surfacing alongside new ones. The enemy is closer than any of them realized, and before the Learmonths can fight the threat outside their walls, they will have to discover who opened the door. Some oaths bind families together. Others hollow them from within.