Rod Tritone is all set to take over the Mer kingdom when his father retires, until the ruling council tells him he has to marry first. The council gives him legs for the duration of his mission, as well as his future queen's address and phone number.

She's Valerie Dumere, the daughter of a Mer father and a human mother who raised her in landlocked Kansas. When devastatingly handsome Rod Tritone shows up and tries to tell her about the kingdom under the sea, not only does she think he's crazy, she's determined that's the last place she'd ever want to go.

Then a vicious squad of seagulls tries to stop the Mer Prince from inheriting his throne and Val finds out about her true nature. Now she has to make the choice of a lifetime - stay on land, or follow Rod to his underwater world...