Spartakus and the Sun Beneath the Sea revolved around two children, Matt and Rebecca, as they tried to save an underground race of humans known as Arkadians from certain doom, as their artificial sun was beginning to fail. With the help of Tehrig (a fully sentient flying robot vehicle), Arkana ( Avatar of the Arkadian peoples) and Spartakus (A lone nomad), Matt and Rebecca try to find a way to save the Arkadians, all the while running from a band of scavenging pirates.