A group of people, along with a smart computer named IO, were sent to the Moon to fix it up and come up with technology to save Earth. Three generations later, the Moon people, living in Moon Haven, have a great society while Earth still struggles. A girl named Chill steals a strange gadget and is fatally harmed by her boyfriend Strio, leading to the first murder in Moon Haven. Law enforcers Arlo and Paul track down the culprit and arrest Strio.