Obedience has always been a matter of survival for sixteen-year-old mermaid princess Pauline. Her mother is the tyrannical Queen Calypso, who rules the kingdom of Atargatis with an iron trident. To utter one word against her would mean banishment—or worse—so Pauline bites her tongue and minds her manners. But on the eve of her sister's merling-shower, all of that is about to change. Confronted with the truth about what happens to the human men who are betrothed to the mermaids of Atargatis, Pauline realizes she can stay silent no more.

Determined to end the queen's dark tradition, Pauline goes along on a search for shipwreck survivors, secretly planning to free them. But things get complicated when she finds herself inexplicably drawn to one of the men. Before she realizes what's happening, she has kissed him—and a kiss from a mermaid is not without consequences. Now Pauline will have to risk everything if she is to save the young man and thwart the queen's dark plans…