A mysterious car has been spotted on the roads of the USA—it races twice as fast as any racing car. Off the coast of America, a ship of an unusual streamlined shape has been discovered, floating without the help of wind, steam, or a kerosene engine, and it slips away from any chase. In a lake isolated from the water system, the presence of a submarine has been noticed… How are all these events connected with each other, and with the mysterious flashes of fire in the impregnable crater of Mount Great Eyrie?