Arsène Lupin III, the world-renowned thief, sets his sights on a legendary artifact known as the Bresson Diary. This diary is believed to hold the secrets of an immense treasure, and Lupin's quest begins when he manages to outmaneuver police inspector Zenigata during an elaborate heist. However, the diary is locked, and only a special key can open it. Joining forces with a young archaeologist named Laetitia, who has her own reasons for seeking the diary, Lupin travels across the globe, facing off against a secret organization and a malevolent scientist who are also after the treasure.

As they dodge relentless pursuers and solve intricate puzzles, Lupin and his team, which includes master swordsman Goemon and expert marksman Jigen, uncover the diary's mysterious connection to Nazi Germany. Their adventure leads them to dangerous locations, from hidden chambers to ancient ruins, as they race against time to unlock the secrets contained within the diary. Along the way, alliances are tested, and hidden truths come to light about Laetitia's past. With danger at every turn, Lupin's wit and skill are put to the ultimate test in a high-stakes chase that could alter the course of history.