The old forester Ferdinand Aiblinger has seen a lot in his long service. He is currently on the trail of smugglers, but this time he has to discover that the suspect is a harmless tourist from Berlin, is called Emil Zoppel and is at least as old as he is. Zoppel is extremely harmless, he is with his wife Mathilde only on vacation in the Bavarian mountains. Together with a servant and Aiblinger's two nieces Barbara and Gretl, the unsuspecting piglet wants to track down an owl that can be heard especially at night (but which in truth doesn't exist here at all).