Der Feuerteufel

Lena and Willi visit the somewhat strange Madame Brickabrack during the vacations. The old lady, who is well known in town, owns a junk store in which there are all kinds of things to marvel at. One of them is an old cupboard that supposedly allows you to travel back in time. And indeed: just a moment ago the children were in the magic cupboard and now they are suddenly standing in the middle of a country lane. There they are already awaited by the siblings Martha and Karl, who think they are relatives. But Lena and Willi don't have much time to get used to everyday life in the twenties: An arsonist is up to mischief in the area and puts all the villagers in fear. Suspicion falls on the strange blacksmith. Lena, Martha, Willi and Karl form the "Four-Winged Gang" and soon realize that the case is not that simple. Will they succeed in convicting the real firebug?