Atlanteans had rescued from a ship sunk in the war, fifty years previously. Muggins tells Don that the people call their town Mlayanu and he introduces him to K'mith, the president of Mlayanu. Don discovers that K'mith, his family, and several other Atlanteans speak English, having learned it from Muggins in order to read the books that they find in sunken ships and to understand the radio messages that they pick up occasionally through a floating antenna. Because Shep resembles the dog-god that the more superstitious Atlanteans worship, it is decided that Don and Shep will live with K'mith and his family. In K'mith's home he meets K'mith's wife and twelve-year-old daughter and his nephew S'neifa, the son of his deceased older brother K'mayo, who had rescued Muggins. As Don gets settled into K'mith's house, S'neifa tells him how an outcast European tribe, some 28,000 years ago, made some accidental discoveries that enabled them to live underwater and develop the Atlantean civilization. Because he's under eighteen, the Atlanteans assume that Don is uneducated, but S'neifa suspects and then confirms the truth. He then gives Don a copy of a radio message that the Atlanteans have picked up: it tells Don that the garbled distress call from Triton had been misinterpreted and that the United States has accused another country of capturing the submarine. Later Don goes for a walk with Shep and finds the building where the town's dome is created and controlled open and unguarded. Sneaking around inside the building, he discerns how the system works and he takes a discarded diagram as he leaves. That evening he takes the diagram to show to Dr. Drake and his uncle. Little can be gleaned from the diagram, but the men do discern that the forcefilm could protect a city from a nuclear attack. Returning to K'mith's house, Don tells K'mith of the discovery, but K'mith already knows about it. As for Don's plea to let the Triton and her crew return to the surface, K'mith shows Don another intercepted radio message: the United States and the country it had accused of taking the Triton have exchanged ultimatums and nuclear war is less than a week away. That night S'neifa brings Don a bubble suit so that he can free the Triton'''s crew from the small bubble-dome in which they are imprisoned. At a certain signal S'neifa will activate the forcefilm