In 2006, Mutta Namba and his brother Hibito spot a mysterious UFO and promise each other that they will both become astronauts when they grow up. Nineteen years later, it is 2025. Hibito has become an astronaut, fulfilling his part of the dream. He is on his way to leave his mark in history as the first Japanese person to walk on the moon as a member of a team of astronauts on a long-term mission to the moon. Meanwhile, Mutta has been going through a rough spot in his life after getting laid off from his job. Soon, a letter of acceptance to JAXA astronaut testing is sent to Mutta. Hibito, who hasn’t given up on their childhood promise, had sent in his application. Mutta, who had once given up on becoming an astronaut, once again decides to pursue his dream.