Pingo is fishing, and Pingu meets up with him by the water. Pingu spots a bottle bobbing up and down in the water, and throws snowballs into the water to float the bottle to the shore. He smashes the bottle, and finds a mysterious map inside. This shows a route from the water into the hills, with a big “X” at the end point. Pingu and Pingo follow the route, which is quite hazardous in parts, to a boarded up cave. Pingu goes into the cave and discovers a padlocked chest. He brings it out and breaks into it, but he and Pingo are both disappointed to find that the chest is empty except for a shell. They then have a difference of opinion over who gets what, as they both want the chest; Pingo eventually takes the chest and Pingu the shell. When Pingu gets home with the shell Pinga is quite keen to have it, but Pingu won’t give it to her. Mother comes over and he gives it to her, but Pinga tries to grab it and it falls to the floor, breaking open. They’re all surprised to see a pearl drop out and roll across the floor. Pinga rushes to get it and gives it to Pingu, and they’re all pleased at their good fortune.