The year is 2068. People have been building homes on the moon for at least four decades. Amongst these people are three kids. The youngest is Apollo, aged 8. His older brother is named Spacey, aged 12. And last of all, Halley, who is Spacey's twin sister. These three kids have one thing in common. The same condition as their father, which makes them allergic to air. Because they are different, they are a target for bullies at school. They soon have the chance to escape from the bullying and begin a new life on the brighter side of the moon, which turns out to be an amusing and exciting adventure for the three siblings.