Lupin heads to the Mediterranean island of Colcaca in pursuit of a box said to contain a draft of Ernest Hemingway's final, unfinished novel which supposedly describes the author's last journey and his discovery of great riches. Unfortunately, the island has been under siege by would-be treasure hunters for ten years. These are divided into two factions, led by self-appointed president Carlos and his rival, the warlord Consano. They do not take kindly to intruders, and have turned the island into one big battle zone.