When a space mission in Wonder Woman’s robot plane goes awry, the heroine saves herself and two sister Amazons from falling into the sun by diverting their course to land them on Mercury. There they become prisoners of the giant Mercurian males, led by King Celerito, who have enslaved all their women. Wonder Woman breaks free, encircles Celerito with her magic lasso, and orders him to release her sister Amazons and the Mercurian women. The ladies of Mercury give Celerito and other males a taste of menial work, but Wonder Woman tells them to live with them in love and peace and equality shortly afterward. Then she and the two Amazons return to Earth.
Wonder Woman discovers a miniature sun in the crater of an atomic bomb test and recovers it for study in Paradise Island. The Amazons discover that an atom of uranium from the sun is really a miniature planet, controlled by female “protons” led by Queen Atomia, who have enslaved the male “neutrons”. Atomia directs the atom-world into a beaker of water in the Amazons’ laboratory, creating a vapor that kayos the Amazons and shrinks them into “protons”. She binds the Amazons and has them taken prisoner, telling Wonder Woman she intends to enslave her and use her to master the Earth. Wonder Woman uses a telepathic command to have the “neutrons” free her, after which she frees the other Amazons, enlarges them and herself, and returns with them to Paradise Island.