Two mysterious figures approach Lupin with a threatening invitation. It turns out that they’re messengers of Arsène Lupin I, Lupin’s grandfather! But what game is afoot?

Lupin must lay low. He decides to build a secret base for Jigen and himself at school, however, making a hideout is more complicated than he expected...

Around Christmas, Lupin III meets a strange tattooed man. Meanwhile, a weapon has been stolen from a US military base by Lupin II.

With minutes left until the atomic cannon is fired, Lupin takes a step toward becoming a great thief.