Now that Nikki has rescued Jack, all she wants is to be with him and graduate high school. But after being tricked by Cole, she's begun the process of turning into an Everliving herself . . . which means she must feed on a Forfeit soon—or die. Nikki and Jack begin a desperate attempt to reverse the process, using everything they can think of. Even Cole, who they expected to fight them at every turn, has become an unlikely ally—but for how long? Nikki needs to feed on Cole to survive, Cole needs Nikki to gain the throne in the Everneath, Jack needs Nikki because she is everything to him—and, together, they must travel back to the underworld to undo Nikki's fate and make her mortal once more. Will Nikki be forced to spend eternity in the underworld—or does she have what it takes to bring down the Everneath once and for all?