Gretchen may have known she was a descendant of Medusa long before her sisters—after all, she's spent her life fighting the monsters that escape the abyss—but that doesn't mean it will be easy to teach the other girls the ropes. Can she rely on Grace and Greer, or even trust herself to keep them safe? Greer has pressing social commitments on her plate and precious little time to train in her newfound powers. But that wretched second sight won't leave her alone, and her fabled heritage seems to be creeping into her fashionable life. Grace has worries closer to home—like why her brother, Thane, has disappeared. He's hiding something. Could it possibly be related to the secret heritage the triplets share? With the warring factions among the gods of Olympus coming for them, the creatures of the abyss pushing into their world, and the boys in their lives keeping secrets at every turn, the three girls must figure out where their fate will take them and how to embrace the shadows of their legacy.