Appu & Gappu are siblings from Rainbow planet, who found their way to earth after their planet was taken over by Galaxy monster 'Planeter'. The kids were found by Uncle Gomes, who raised them as his own. Under his shelter, Appu and Gappu now live in a huge palatial house in the outskirts of a remote town. They have been trained in the art of self-defense and warfare. They are brighter than any kid their age. Being from another planet, the kids have always been curious and given their special abilities they find themselves better suited for solving the various mysterious crimes. Now, at the age 11, they have become the most popular detective duo, the world has known.