Captain Andrew and his crew journey in the undersea vehicle to study the underwater activities. But soon they heard a call for help from three mermaid sisters (Uniqua, Ramona, and Penny). They took them to the Mermaid Kingdom where King Austin tells them that a series of quakes is threatening the kingdom. Can Andrew and his crew find out what's causing the shaking?
This episode article is in need of a synopsis. A synopsis is intended to be a very detailed description of what occurs in the episode.