A GREAT LOVE. A PALACE BENEATH THE SEA. A DEVASTATING BETRAYAL.

A doomed love story created the city of Ys, it's fitting that another one would end it . . .

Nolwenn is sure that her life's purpose is to defend her beloved city of Ys as a lighthouse keeper. But when a dangerous tide threatens Ys, the queen instead tasks Nolwen with collecting enough rare seasilk to shield the city from deadly sea monsters.

Determined to fulfill her task, Nolwenn recklessly puts her life in danger and is attacked by sea monsters. She's saved by Morvan, who is a korrigez, and has the torso of a human and the tail of a fish. Against her will, Morvan drags her deep beneath the sea to the coral palace of Below-Ys. Although terrified and homesick, Below-Ys is strange and beautiful - and so is Morvan. The more time Nolwenn spends below the surface, the less she is sure she wants to leave.

As danger draws ever nearer and Ys remains precariously unprotected, Nolwenn must decide between her heart and her home.