Tim, Lotte and Floor Bouwman find out that something is wrong at the camping site of their grandfather Darius. Also strange things occur in the forest. Soon they meet secret allies hiding in the forest and trying to figure out together what is going on. Gradually, the children discover that the company Gentopia has everything to do with it. And that Director Cleo King is a lot less innocent than she seems. The kids do everything to find the truth and help grandfather Darius and his campsite, the forest and even save people and animals from extinction.