Inspector Koichi Zenigata, a Japanese police inspector affiliated with Interpol, dedicates his career to capturing the master thief Lupin III. His character embodies relentless pursuit with unexpected complexity across franchise iterations. Zenigata hails from an unspecified Japanese city, initially serving with the Tokyo Metropolitan Police Department before transferring to Interpol to track Lupin globally. He is depicted as a descendant of the fictional Edo-period detective Zenigata Heiji, inheriting a legacy of law enforcement, though later series downplayed the direct blood relation in favor of the name Koichi Zenigata. His obsession with apprehending Lupin defines him, often leading to disregard for personal safety or professional protocols. Despite frequent failures, Interpol respects him for inadvertently dismantling other criminal operations during his pursuits. Physically, Zenigata presents as a middle-aged man of average height (approximately 5'10" to 5'11") with a muscular build, square jaw, and signature cleft chin. His appearance varies slightly across adaptations, consistently featuring dark hair, often in a flat-top or comb-over style, and attire typically comprising a trench coat, suit, and fedora. The color schemes of his attire change per series iteration (e.g., orange in Part 1, camel in Part 2, red in Part 4). He demonstrates notable physical abilities, excelling in judo, karate, and marksmanship with a Colt M1911 pistol, and employs a trademark technique of throwing handcuffs with bola-like precision to immobilize targets. Zenigata's personality balances competence and comedic impulsiveness. Early portrayals (particularly in the manga and Part 1) show him as ruthless, corruptible, and violently obsessive. He evolves over time into a more affable, principled figure—highly sensitive, prone to emotional outbursts or tears, especially when Lupin appears dead or shows him kindness. He adheres to a strict moral code, rejecting bribery and prioritizing justice over orders. This integrity prompts him to resign or operate independently when Interpol obstructs his Lupin pursuit. His single-minded focus manifests in extreme behaviors: enduring poverty for investigations, undergoing cryogenic freezing to chase Lupin in the future, or retiring as a monk upon believing Lupin dead (as seen in *The Fuma Conspiracy*). His dynamic with Lupin is adversarial yet symbiotic. While publicly vowing to arrest Lupin, Zenigata privately respects him and refuses to let others harm or capture him. Lupin reciprocates with grudging admiration, frequently rescuing Zenigata from mortal peril and affectionately calling him "Pops." This mutual regard establishes an unspoken rule: neither attempts to kill the other. Instances of forced cooperation—such as exposing Count Cagliostro's counterfeiting ring or navigating time travel in *Elusiveness of the Fog*—highlight their capacity for temporary alliance against greater threats. In *Elusiveness of the Fog*, Zenigata is transported 500 years into the past alongside Lupin's gang due to a villain's time machine, compelling them to collaborate to restore the timeline. Zenigata's personal life remains underdeveloped. *The Mystery of Mamo* references a daughter, Toshiko, though this is rarely revisited. His dedication to Lupin's capture precludes lasting relationships, though episodic encounters (e.g., Part 2's "The Woman Pops Fell in Love With") explore fleeting romantic possibilities. He exhibits habits like binge eating during depression, messy living spaces, and occasional heavy drinking. Notable character explorations include Part 5's "Zenigata, Gentleman Thief," where amnesia leads him to emulate Lupin's thievery, and Part 1's "One Chance for a Prison Break," where capturing Lupin leaves him unfulfilled and paradoxically desiring his escape. These narratives underscore his existential reliance on the chase.