The adventure begun in Bewitched in Oz (2014) continues with Zerie Greenapple and her friends embarking on separate missions in an attempt to prevent Glinda the Good (who, it turns out, is not so good) from wresting control of Oz. Zerie is turned into a mermaid by Ozma and journeys through Aquarius, an underwater kingdom beneath Oz, towards Glinda's palace, hoping to rendezvous with her friends. Double crosses and deceptions make Zerie's task more complicated. Familiarity with the first book is not necessary to follow this story, and fans of mermaid stories will be attracted by the underwater backdrop, where most of the action is set.

Separated from his friends outside Glinda's castle, Brink awakens alone and imprisoned. Meanwhile, unexpected help from Ozma reunites Zerie and Vashti with Tabitha. They plot against Glinda, who they now realize is evil, and create a three-pronged attack with pearls from the mermaid queen. Burns's second re-envisioning of Oz, though overcrowded with incident and characters, provides a strong theme of friendship to a fast-paced adventure.