Lili's connection to Anjidia is gone. In the wake of the failed rebellion, she's been forced into hiding, and the new regime has grown bolder in her absence. To locate the missing rebels who supported her, and to have any hope for a second chance to save Anjidia, she must find a way to restore her gift.

When the mysterious Naltans extend an unprecedented invitation and an offer of help, Lili and former lieutenant Gabrien set off for their underwater city. The welcome is warm and the city full of wonders, but the more Lili learns about the merpeople, the more she questions their motives.

As tensions climb, Lili and Gabrien discover the unsettling truth about the Naltans, the regime, and the rebels. With an ocean between them and the air above, will the merpeople prove to be their friends—or their captors?