What makes Lake Constance so attractive for animals? Like a magnet, this big lake attracts hundreds of thousands of migrant birds. Their routes lead across Europe. Three hundred different bird species start and land here. For them, the lake is an interstation, a breeding area or a wintering ground. During the night, other dwellers become active, such as the racoon or the beavers. For centuries, eels have wiggled on the banks. This documentary penetrates into the micro-cosmos of Lake Constance and presents amazing pictures of the fascinating actions under, on and above the water.