Two tween boys Nate and Tyler are forced together by their parent’s relationship. As they explore the beach one day they meet Travis and Sarah. That night they take them to their secret spot in the harbor. As they explore the harbor, they find something unusual in the waters. It’s a mystical sea creature and she’s injured. They know they must help her and reunite her with her family. They bravely go to extreme lengths to protect her from selfish scoundrels set on capturing her and even harming her for their own profit. Ultimately it pulls this family together and they save Mysti.