Infamous master thief Lupin Sansei is back once again to do some grand thievery, now in San Marino, Italy. Only this time he's stealing... Love? Rebecca Rossellini, a famous heiress and businesswoman, is now married to Lupin, much to the surprise of Lupin's gang who were invited to the wedding, and Interpol Inspector Zenigata Kouichi, whom has not yet given up on catching Lupin, and even went as far as to crash the wedding in order to give his objection. But did Lupin really fall in love with a woman other than Mine Fujiko? Surely he must have something up his sleeve, right? That's what his right-hand man Jigen Daisuke believes, and the swordsman Ishikawa Goemon wants to believe this as well. One thing is for certain; He is not the only scheming thief in San Marino. And not only that, but it seems that a cunning MI6 agent, Nyx, is stationed here as well. Just what exactly is in store for Lupin in his Italian adventure?