When communications with the S.S. Aurora are interrupted, Starman is called in to investigate, and he comes face-to-face with the dread League of the Octopus......and the man behind them: the Light!; An evil inventor creates a nefarious black ray ring, which is used to rob a jewelry store, fetching the villain cash needed for his work, including a giant robot named Giganto, which Hourman must overcome or die.; Sandman not only has to save a young man at sea from foreign agents, but also his scientist-father, who has discovered a way to extract magnesium from the ocean.