The Chameleon Comes to the Rescue - H. de Roos

When a large, dangerous fire breaks out near the lake, twin brothers Hielke and Sietse don't hesitate for a moment. Together with their super-strong boat, the Kameleon, they immediately sail to the disaster site to help wherever they can. Thanks to their courage and swift action, the boys, along with the villagers, manage to prevent a disaster.