A kindly but poverty-stricken fisherman catches a magical fish. The fish begs him to let it go, claiming to be a prince. The fisherman lets it go and tells his wife all about it. The fisherman's wife is overbearing and greedy and she demands that he go back and ask the fish to grant him a wish out of gratitude. The fisherman does not have any desires, so the wife tells him to make the fish give them a nicer house, which is what she wants. Mandje! Mandje! Timpe Te! Flounder, flounder, in the sea! For my wife, good ilsabil, Wills not as I'd have her will."
The German lightship (permanently anchored floating 'lighthouse') Borkum Riff is about to be decommissioned. For his last tour of duty, Captain Johann Freytag brings along his near-adult, estranged son Fred. The ship picks up three men stranded in a broken-down boat--who are armed. The captain tries to avoid trouble, but the crew, his son, and the trio of violent robbers on the run keep rejecting his nonviolent advice, which leads to repeated bloodshed.