Before he became the Master Thief, before he reached global infamy, there was a boy whose decision changed everything...

Lupin III, a bored junior high schooler in Tokyo, takes an interest in a young Daisuke Jigen, a mysterious and impressive marksman. After striking up a conversation with Jigen at a nightclub, the latter concludes that Lupin is simply a privileged and naïve boy from a well-to-do family and doesn’t want anything to do with him. However, while helping the nightclub singer Yoko, who is being pursued by the yakuza, Jigen learns that Lupin is the grandson of a legendary thief…