After finally settling into her new life at the Citadel, Thalia is reunited with her father, who is disturbed at the changes within her. Risking banishment, Thalia must work to prove to her clan and herself that she is still capable of leading them. The problem is, her memories haven't returned, and she cannot shake the feeling that she doesn't belong. Thalia discovers that betrayal runs deep within her clan, just as she sets out to join Joss and Kael in doing the one thing she fears most: track the Septori to save Joss' kidnapped sister. Along the way, she must confront her own fears on a journey of self-discovery that will take her deep into the stronghold of Denai; as they travel to the ancient floating city of Skyfell.