Inspector Juuzo Megure is a high-ranking officer in the Tokyo Metropolitan Police, where he holds the position of inspector leading the First Investigative Division. He is a seasoned and experienced detective who often takes personal command of major cases, directing his subordinates at crime scenes and overseeing interrogations. His rank and presence denote a man who has spent decades in law enforcement, rising through the ranks due to persistence and a solid, if unspectacular, career. One of the most defining physical aspects of his appearance is that he is never seen in public without a hat. This is not a mere fashion choice but a necessity born from an injury early in his career. A case he worked on left him with a prominent scar on his scalp, and he harbors a lasting self-consciousness about its origin, making the hat a permanent part of his uniform.

In terms of temperament, Megure is a grounded and dedicated professional who treats his work with serious resolve. He is known to be a capable leader who shows genuine concern for the members of his team, which includes detectives like Wataru Takagi, Miwako Sato, Ninzaburo Shiratori, and Kazunobu Chiba. While he maintains an authoritative presence, he is not immune to displaying frustration. When investigations become unpredictable or complicated, he can have occasional outbursts of temper, reflecting the intense pressure that comes with managing high-stakes cases. As an investigator, his methods tend to be traditional and procedure-driven. This conservative approach is effective for routine police work but can sometimes limit his ability to think flexibly when faced with unconventional criminals or elaborate schemes.

His role in the crossover story is primarily that of the local authority figure coordinating the official response to the intrusion of international criminals into his jurisdiction. When a challenge letter arrives announcing that the legendary thief Arsene Lupin III intends to steal the priceless Cherry Sapphire jewel from a bank in the Beika district, Megure is put in charge of the defensive operation. He takes the threat seriously and mobilizes his forces to secure the gem and apprehend the thief. Understanding the unique challenge that Lupin III presents, Megure takes the pragmatic step of contacting Inspector Koichi Zenigata of Interpol. He collaborates with Zenigata to combine local police resources with the specialized knowledge of Lupin that the Interpol inspector possesses. This cooperation allows for a larger coordinated effort, including assigning detectives Sato and Takagi to assist in safeguarding the jewel.

Several key relationships from his regular duties carry over into this crossover. He has a long-standing professional history with detective novelist Yusaku Kudo, having occasionally consulted him on difficult cases in the past. This connection inadvertently continued with Yusaku's son, the high school detective Shinichi Kudo, whose insights Megure came to rely on. By contrast, he is often dismissive of the young Conan Edogawa and the group of child detectives known as the Detective Boys. Despite their proven helpfulness in resolving cases, Megure typically views them as nuisances who interfere with serious police business. He also holds reservations about the private detective Kogoro Mouri, often associating his presence with the occurrence of murder cases.

The two crossover narratives highlight different aspects of his function. In the television special, his role is more facilitative, helping to set the larger plot in motion. When Kogoro Mouri's daughter, Ran, becomes entangled in the affairs of the European kingdom of Vespania, Megure steps in to assist. He uses his personal connections to arrange for Kogoro to travel abroad, introducing him to Inspector Zenigata. The two inspectors share a history from the police academy, and Megure leverages this relationship to have Kogoro join Zenigata as a makeshift assistant, allowing the worried father to follow his daughter. Additionally, when a poisoning attempt is made on Princess Mira at the Sakurasaku Hotel, Megure is present at the scene, leading the initial investigation before the true culprit is exposed through other means.

In the subsequent film, his activities shift from facilitator to operational commander. As Lupin III executes his heist, Megure oversees the tactical response. He ensures that his department provides full support to Zenigata's pursuit. Even after Lupin successfully steals the jewel by disguising himself as Officer Takagi, Megure continues to manage the aftermath, directing the investigation and implementing containment procedures. His focus is always on maintaining order and applying the full weight of the Tokyo police to the situation. While he may not be the genius who unravels the master thief's complex plans, he represents the persistent and unwavering arm of the law, providing the structural backbone against which the more unconventional characters operate. His decades of operating experience allow him to manage his subordinates effectively and coordinate with international authorities, even if his traditional methods are frequently outmatched by the extraordinary circumstances that arise.