Princess Lira is siren royalty and the most lethal of them all. With the hearts of seventeen princes in her collection, she is revered across the sea. Until a twist of fate forces her to kill one of her own. To punish her daughter, the Sea Queen transforms Lira into the one thing they loathe most - a human. Robbed of her song, Lira has until the winter solstice to deliver Prince Elian's heart to the Sea Queen or remain a human forever.

The ocean is the only place Prince Elian calls home, even though he is heir to the most powerful kingdom in the world. His calling? Ridding the world of the menace of the sirens. But when he rescues a drowning woman, it becomes clear that there's more to her than there first appeared.

She promises to help him find the key to destroying the sirens for good. But can he trust her?