Sealah Loveridge isn't your average teenage girl- she's a mermaid princess, and the first in line to inherit her mother's crown. And though that sounds like a dream come true, it's actually not, because someone within their secret little seaside kingdom resents all of the blessings that have been bestowed upon Sealah, and that person just happens to be the most popular girl in their exclusive school- and there's nothing she wouldn't do (or hasn't already done) to wreck Sealah's so-called 'fairytale' life. And since Mariah Grey started telling everybody that would listen that Sealah Loveridge was initially named after a sea monster from Greek mythology 'Scylla,' Sealah has been killing herself trying to prove that she's not a monster at all, even though that has basically meant retreating into her own little, lonely and thanks to Mariah- loveless- world, where all she does and work and dream.
By her seventeenth birthday, Sealah has become a shadow of her formerly over-achieving self, and knows that if something doesn't change soon, then she'll never get to grow up to be just like her mother Ivyanne, who just so happens to be the most perfect, vivacious and enchanting mermaid in the world. Things could turn around, she knows, if the unveiling of the amusement park she has been working to open on the boardwalk goes well, and if she can manage to secure herself a perfect prince from within the Marked boys… but how is she going to accomplish anything, when it feels like at every turn, her rival Mariah Grey is not only attempting to sabotage her- but succeeding?
The amusement park was supposed to be Sealah’s greatest accomplishment, but unfortunately, with the influx of visitors to the Seaview area comes a dark evil, and Sealah quickly works out that if she is going to get through the opening weekend while Mariah is hell-bent on turning it into a witch-hunt, she might just have to give up on the idea of being everybody’s perfect mermaid princess, and embrace the sea-monster siren that still dwells within- and the loneliness that comes with it- instead.
This could end up being a summer that Sealah will never forget... but only if she manages to survive it.