Many years ago, two planets at the other end of the Milky Way were swallowed by a black hole, and two alien children who were still in their infancy came to Earth in a spacecraft. They grew up in completely different environments with superpowers, which also created their own different personalities and life directions. When they grew up, the dignified and upright one became the city superman (voiced by Brad Pitt) who defended the peace of the city, while the wretched-looking, blue-skinned big-headed one became the big bad guy McMahon (voiced by Will Ferrell) who destroyed the well-being of the people. They fought all day long and the war continued. On the opening day of the City Superman Museum, McMahon successfully escaped from prison and hijacked the beautiful female anchor Roshan (voiced by Tina Fey). In the final battle of the observatory, McMahon successfully defeated his old opponent for many years and completely dominated the city. The good times did not last long, and McMahon, who lost his opponent, soon felt dull. Inspired by Roshan by chance, he decided to create a new hero of justice and restore the happy days of the decline. However, everything began to develop in an unpredictable direction...