: If the girls help her, Aquamarine will grant them one wish—which they hope to use to keep Hailey from moving.

After a violent storm, the girls discover a beautiful, sassy mermaid named Aquamarine (Sara Paxton) washed into their beach club's pool. Aquamarine has fled an arranged marriage and has exactly three days to prove to her father that "true love" exists so she can stay on land. In exchange for their help in winning the heart of the handsome local lifeguard, Raymond (Jake McDorman), she promises to grant the girls one life-changing wish.

Five years later, Claire is about to leave for college, and Hailey visits their old beach town one last time. The pool where they hid Aqua is now condemned. But on the last night, a glowing blue light appears in the water — along with a shell covered in writing:

Aquamarine and Finn had decided to escape, and were planning to build a new life together, free from the constraints of their royal families. Luna promised to keep their secret, and offered to help them in any way she could.

: Unlike many romance-driven films of that era, the story concludes with the revelation that the "love" Aquamarine needs to prove exists is the genuine friendship between the two main characters, Claire and Hailey, rather than a romantic spark with Raymond.

La aquamarina es una piedra preciosa de color azul claro a azul verdoso que se encuentra en rocas graníticas y pegmatíticas. Es conocida por su belleza y su capacidad para reflejar la luz de manera única.