Arsène Lupin III, the globe-trotting master thief and grandson of Maurice Leblanc's fictional gentleman thief, thrives on audacious heists. His heritage includes conflicting accounts, one suggesting Japanese ancestry via his grandmother Mylene Lupin's marriage to Kawamuko farmer Jirokichi – a claim made during deception and unverified. His lineage traces back to his grandfather, who built the Lupin Empire through amassed treasure, later squandered by gambling and extravagance.

Lupin III possesses exceptional talents: mastery of disguise, expert marksmanship with his Walther P38, remarkable agility, multilingual fluency, and encyclopedic knowledge. These skills fuel his complex capers, consistently outwitting authorities and rivals. His personality blends thrill-seeking daring with flashes of altruism; driven more by the challenge than material gain, he has surrendered treasures to rightful owners or the needy. Despite frequent betrayals, especially from Fujiko Mine, he remains fiercely loyal to his core team (Daisuke Jigen, Goemon Ishikawa XIII) and holds deep respect for his relentless pursuer, Inspector Koichi Zenigata, valuing their defining rivalry.

In *Napoleon's Dictionary*, Lupin targets a dictionary once owned by Napoleon Bonaparte, famed for omitting the word "impossible" and rumored to hold a hidden clue to his grandfather's treasure. This connection is deeply personal: Lupin's grandmother concealed the treasure's location within its pages after her husband's gambling depleted their fortune. This quest draws Lupin III into a high-stakes French classic car race where the dictionary is the prize, underscoring his fascination with family legacy and grand challenges.

His portrayal evolves across media, ranging from the original manga's darker traits (remorselessness, sexual aggression) to anime adaptations' more chivalrous, comedic antihero. Regardless of iteration, his core identity persists: a thief who relishes freedom, outlandish schemes, and the perpetual pursuit by Zenigata.