After a long time, invitations come from Lupin III, and Jigen Daisuke, Ishikawa Goemon, and Mine Fujiko are reunited aboard the luxury liner Sirloin. But when Lupin appears afterward, he tells them that he was himself invited by Fujiko. Why have they received false invitations? Trapped aboard the ship together with their eternal rival, Inspector Zenigata, the moment of confrontation with their bitter rival Mister X (the commissioner of Scorpion) is fast approaching!