A general arives in the port of Sao Mareno, the capital of Aquantina, with a disk for archeologist Dr. Acosta. The disk contains hieroglyphics showing the whereabouts of the ancient treasure of Panaqua. The treasure is guarded by Panaquan tribesmen, but because it is desired by the evil Octopus, the government wants to place it in the museum. Shelley gets the Neptunes to Pier 213 instead of 312 (for their trip to Aquapuclo), and they join Dr. Acosta on his quest. The Octopus, who drives a submarine shaped like a squid, with working tentacles, traps Acosta's ship, and Jabberjaw is ejected by the automatic trash ejector as Acosta's sub fills with water. Jabberjaw rejoins them in Acosta's aquavan (like an escape pod) but is later captured and duplicated by the Octopus, who obtains the disk, but not before an imprint that Acosta can use is left in Jabberjaw. The gang fights hostile tribesmen but find the computer left by a previous expedition, which leads them to the central pyramid.