While journeying north toward the Dark Queen, Guinevere falls into the hands of her enemies. Behind her are Lancelot, trapped on the other side of the magical barrier they created to protect Camelot, and Arthur, who has been led away from his kingdom, chasing after false promises. But the greatest danger isn't what lies ahead of Guinevere-it's what's been buried inside her.

Vowing to unravel the truth of her past with or without Merlin's help, Guinevere joins forces with the sorceress Morgana and her son, Mordred-and faces the confusing, forbidden feelings she still harbours for him. When Guinevere makes an agonising discovery about who she is and how she came to be, she finds herself with an impossible choice: fix a terrible crime, or help prevent war. Guinevere is determined to set things right, whatever the cost. To defeat a rising evil. To remake a kingdom. To undo the mistakes of the past even if it means destroying herself. Guinevere has been a changeling, a witch, a queen-but what does it mean to be just a girl?