Kirabo is back for her scariest adventure yet. This time she's in the middle of waring merpeople and must face a fierce sea serpent.
After falling out with Brady, Kirabo decides to spend some time alone on a tropical island, but her peace and quiet is soon forgotten as she meets Kiristabel, a beautiful mermaid with a dark secret. Kirabo suddenly finds herself in the middle of a war between the mermaids and the mermen. Just as Kirabo begins to think things couldn't get any worse Brady appears on the side of the mermen. Kirabo and Brady must become friends again and bring an end to the war, but to do that they must face a dangerous sea serpent and steal it's magical pearl.