United States Navy submarine R-93 dives into the ocean. Something goes wrong, and the dive continues down past a safe depth. The submarine begins to fail. Captain Small, Huey, and Robert Crane are rescued by Atlantean Fishmen. Ssil-Il is one of their rescuers, along with two other Fishmen by the names of Lor-Shim and Fen-Ac. They are taken to the domed city of Atlantis. Shar-La, Queen of the city of Atlantis, greets them. She talks to Crane, informing him the Atlanteans had lost their once advanced technology, and would die in four years if they could not get it working.