In 2085, an organization called the World Catastrophe Killzone Department (Wicked) has cared for and raised so many children since 20 years ago. The children never saw the outside world again and were strictly forbidden to leave the Wicked building. Because of that, some of them began to feel that Wicked was hiding something and began investigating it until they finally found a secret that made them determined to change it by going back to the past. With hope amid chaos, they race against time. Will their plan succeed? Or will Wicked find out and try to stop them?