Fujiko obtains a file that records the location of the legendary Columbus Egg, a mystical relic that can control the weather. To prevent a sinister villain from seizing it, she recruits Lupin and the gang to find the long‑lost treasure. In an attempt to keep the file safe, Fujiko memorizes its contents and burns the original, but the process leaves her with amnesia. Her personality shifts and her memories of Lupin and his friends are almost entirely erased. The team must restore Fujiko to her former self before the Egg falls into the hands of a madman.