There is an NRI couple who come to Vizag on a research project. Their daughter and her cousins love playing in the beach. The kids listen to the story of a lighthouse in the beach which was once used by the sea pirates. But that lighthouse is not in use any more. One stormy night they observe that the lighthouse is functioning.
They suspect that sea pirates might be operating using the lighthouse. The kids start investigating from the next day onwards. The rest of the story is all about how the kids unearth kidnapping and smuggling activities.