Heartless. Until Cassandra awakened the memory of his human emotions, Jack willingly hunted and killed the enemies of the Lady of Twilight, a witch who locked his beating heart away along with all his pain. Now Jack has won a temporary reprieve from the Lady so that he and his giant friend, Minnow, can find the fabled city of Argent, where Cassandra languishes inside a dark tower. With time running out, Jack must ally with Moribrand, a charlatan he once stalked. Their desperate search leads them into treacherous mountains where wind spirits control the skies and powerful wizards battle to locate Argent first. In the quest to prove his heart to Cassandra, Jack may remember how easily it can be broken.