Lupin III and his friends head for the Bermuda Sea, aiming for a "mysterious island" that does not exist on the world map. The goal is to uncover the identity of the mastermind who has been sending assassins to the island and to uncover the vast treasure that is hidden there. However, just as they approach the island, their plane is shot down by snipers, and the group crash-lands on an island of death. What they find...