The sea has always called to Cari. Like a lullaby that only she can hear, she has been drawn to the water's edge for as long as she can remember. Yet fear holds her back from stepping into the sea, until she decides she needs answers that she suspects only the sea can provide.

When her memories return, Cari finds herself in the midst of a far more complicated world than she ever imagined. Her family, the royalty of the kingdom of Piscea, are being held prisoner by the Mad King Varan - a power-hungry merman bent on conquering the five merfolk kingdoms.

Upon her return to the sea, Cari experiences dreams of the Sea Witch, a terrifying creature who pronounces that she cannot possibly stop King Varan from taking over the kingdoms. Can she and her new allies pull off their daring rescue mission? And if they do, what consequences will the Mad King reign down upon them?