Donald buys an ancient amulet with an image of a peninsula. A cross mark and the old writing clearly hint at a treasure. Huey, Dewey and Louie presently realize that the shape of the peninsula matches the map of Florida. So the Ducks travel to the Everglades where they search for the treasure, but to no avail. However, they find a fish-eating dinosaur who has remained unnoticed far from civilization. By accident the amulet opens and shows the brave treasure hunters a picture of an ancestor of the dinosaur. The “treasure” has been found, but Donald and the boys keep the secret for themselves and leave the dinosaur behind in the swamps.