Inspector Koichi Zenigata, a dedicated officer of Interpol and the Tokyo Metropolitan Police Department, is renowned for his relentless pursuit of the international thief Lupin III. He graduated from the same police academy as Inspector Megure, underscoring his extensive law enforcement career. Zenigata exhibits superhuman tenacity in his single-minded chase, exemplified when he recovers from a stun gun shock powerful enough to fell an elephant for thirty minutes within mere seconds. Despite occasional bumbling, peers respect his expertise in criminal apprehension; he has independently exposed security flaws and dismantled numerous criminal operations outside his Lupin obsession. His investigative style blends impulsiveness with a fierce sense of justice, leading him to refuse bribes and operate with insubordination against corrupt superiors or institutional failings within Interpol. Physically formidable, Zenigata is proficient in judo, karate, and marksmanship, wielding his signature handcuffs attached to a rope with exceptional accuracy. His relationship with Lupin III is complex, marked by mutual yet grudging respect. Zenigata fiercely claims the exclusive right to capture Lupin and suffers profound loss of purpose when the thief appears dead. Their dynamic occasionally shifts to reluctant cooperation against greater threats, like uncovering large-scale criminal operations such as counterfeiting rings, notably observed during the Vespania case. There, his investigation into Lupin's theft of the Queen's Crown became entangled with solving the murders of Queen Sakura and Prince Gill. Beyond his Lupin fixation, Zenigata reveals personal vulnerabilities, experiencing depressive bouts that lead to heavy drinking and chaotic living. His personal life remains largely unexplored, with only sparse references to a daughter named Toshiko or a failed marriage. In the *Lupin III vs. Detective Conan* narrative, Zenigata travels to Vespania to prevent the crown's theft. Collaborating with local authorities and Detective Conan characters—including Kogoro Mouri as his temporary assistant—he helps expose Duke Gerard Musca Vespaland as the true culprit behind the royal murders and the illicit mining of a radar-invisible mineral, ultimately aiding Princess Mira's ascension after Lupin returns the crown. Following the case resolution, he immediately resumes his relentless pursuit of Lupin.