In this story, sirens are beautiful while merfolk are a grotesque combination of fish with a little humanity. Sirens need their beauty to lure humans to their deaths- they sing and captivate them into drowning, taking their hearts just as they die. The hearts then lend them some power and become part of them. However, it does not seem that they need the hearts to live. The Sea Queen has tentacles and magical powers through the trident she carries (think Ursula in the Little Mermaid). She does not care for the lives of her subjects (including her daughter) and merely for the power she holds. Thus, she seems ready to get rid of her heir and keep the power to herself. Latching on to a small mistake of her daughter’s (taking a heart one month early), she imposes many punishments- the worst of which is to make her into a weak human and set her out to do the impossible- take a prince’s heart without her siren powers.
Although Elian is a prince, his life really happens on the sea with his loyal crew. He has a magic compass which can tell him if someone is being truthful and a magic knife that absorbs the blood of sirens and kills them quickly. When sirens die, they return to the sea (their bodies become sea water and sea foam), and this maybe makes them seem easier to kill to the Captain (Elian). Things are about to change when he finds a woman about his age floating in the middle of the ocean all alone. He immediately jumps in to save her, and finds that she is somehow less than grateful and a little spiteful.
Lira is trying to accomplish what her mother has asked her, but the longer she spends with the humans, the harder it becomes. She finds purpose in the quest they have set out on- to find the other eye of Keto, which could match the Sea Queen’s power and end her tyranny. Along the way, she also learns about her own humanity, which she was taught to suppress, and what it means to be human.
Overall, it’s a poignant and really fun fantasy that you can easily lose yourself in for a day or two (because you won’t be able to put it down)! The action builds until the end, and I thought at first that it might be a series, but everything is wrapped up in the end. I actually wish it could be series, because I loved the premise, this alternate magical world, and all the characters- primary and secondary- they were all very well crafted. I highly recommend this book for YA readers of all ages. Aside there is fantasy violence and deaths, there is one attempted sexual assault , but it is not too descriptive/does not get far. While it might be better for older readers, younger YA readers may also enjoy this enthralling fantasy novel.