Plot

Ondina meets with the mermaid council to discuss Zac and Mako Island but she doesn't tell them about Erik and Evie. A young mermaid named Neptina follows her back and volunteers to help. Neppy finds Erik and follows him causing mischief.

Ondina meets with the mermaid council to discuss Zac and Mako Island but she doesn't tell them about Erik and Evie. They give her until the next full moon to break Zac's connection with the island. A young mermaid named Neptina follows her back to Rita's house and volunteers her services to help with the mission. Ondina is left in charge of Neppy but she slips out while Ondina is getting her something to eat. Neppy finds Erik and follows him causing mischief. When Ondina scolds her for it, she takes off so she enlists Zac and Evie's help in the search for her.—grrlpunk

When a young mermaid follows Ondina back to Mako Island after a mermaid council meeting, it could spell trouble with the pod. Ondina's news that they've been given until the next full moon to break Zac's connection to mako Island is overshadowed by the arrival of Neptina who wants to help stop the dangerous merman Zac. Neppy mistakenly traps the wrong merman putting Erik in the awkward position of being unable to help Carly get their drifting boat back to the dock. When Neppy becomes disillusioned with Ondina and swims away, she is on the verge of being discovered when Zac comes to her rescue.