In a small town by the sea, Mandy Rose discovers that she is not ordinary. At a young age, she discovers that she has magical powers. However, for fear of what others might do, she must keep this a secret, even from her own parents. To make matters worse, at the beginning of her senior year in high school, she learns that she turns into a mermaid when she enters water. Although she gains some unexpected friends who learn of her secrets, being a half-mermaid is another secret she must keep from everyone else. As Mandy tries her best to keep everything a secret, life throws twists and turns at her, unraveling everything she once knew and loved. Can she find the courage to keep going, or will she cave under the pressure?