Apart from the Rumplund family, the misunderstood toilet researcher Dr. Mugg lives in the small town of Dasseborg. When the wretched Dr. Mugg is not terrorizing the city, he is forging threads down the sewers riding the speed marvel the Pruttomobile. But hold on, the town's only superhero, Captain Filling, is hot on his heels. Captain Filling may not be the most cunning of heroes, but he has big muscles, a big heart and huge summons - Y-front of course!