Out in the sea lies a rocky island. Professor Petersen arrives here to study the birdlife, but he is disturbed by some bathing ladies, which is why he searches further into the island. In doing so, he enters smuggler Jørgen's refuge, an empty barn where the smugglers are staying. The smugglers assume the professor to be a spy and put Fyrtårnet and Bivognen to watch over him. However, they help him escape and all three of them get away from the island in a boat. Out of gratitude to his rescuers, the professor now takes Fyrtårnet and Bivognen into his home as his two foster children. Stumfilm.dk