TV-Series
Description
The character known as Professor Agasa, whose full name is Hiroshi Agasa, is an inventor and the longtime next-door neighbor and family friend of the Kudō household in Detective Conan. He lives at 22 2-chome Beika Town in Tokyo, in a large residence that doubles as his research laboratory, and he supports himself through a variety of patents and inventions, including video games that the Detective Boys eagerly test. He holds a doctorate in engineering, and his name is a play on that of the mystery novelist Agatha Christie. In appearance, he is an average-sized man with a slightly overweight frame, a bald crown with silver hair around the sides, thick eyebrows, a mustache, a prominent nose, and round glasses, and he is usually seen in his working attire. Though he looks much older, he is actually fifty-two years old. He is unmarried and lives alone, though that changes after a significant character joins his household.

His personality is jovial, caring, and outgoing. He has many friends in his community, a social network that proves useful when he needs to explain the presence of children who are not really his relatives. He is very paternal in nature and genuinely enjoys spending time with the young protagonists, often organizing trips, camping outings, and other activities for them. He has a particular fondness for pasta, especially spaghetti, and tomato juice, and he is known for telling pun-based riddles to the children, who react with good-natured exasperation. He also displays remarkable luck in winning food-related prizes in contests, similar to the fortune some of his friends possess. Beneath his cheerful and slightly absent-minded manner is a dependable and protective man who can be counted on in serious situations.

His central role in the story begins when Shinichi Kudō is shrunk by the APTX 4869 and appears at his door in the body of a child. Agasa is the first person to learn that Conan Edogawa is actually Shinichi, and he is convinced of the boy's identity only after Conan reveals private details known only to the two of them. He advises Shinichi to keep his true identity secret for the safety of everyone around him, helps establish the new identity of Conan Edogawa, enrolls him in Teitan Elementary School, and arranges for him to live with the Mōri family. He also becomes the inventor of nearly all the special equipment Conan relies on, including the voice-changing bow tie, the stun-gun wristwatch, the power-enhancing kick shoes, the turbo-driven skateboard, and the communication badges used by the Detective Boys. Later, when Shiho Miyano escapes from the Black Organization and collapses near his home, Agasa takes her in, learns her history, and helps her begin a new life as Ai Haibara, with whom he then shares his house.

His motivations are rooted in loyalty, affection, and a strong sense of responsibility. He has known Shinichi and Ran since their childhood, and he treats the younger generation almost like family. While he occasionally dreams of becoming wealthy through his inventions, his real drive is to support Conan and Haibara in their difficult circumstances. He provides them with a safe home, technical support, transportation in his beloved but unreliable Volkswagen Beetle, and an emotional anchor. Although he does not confront the Black Organization directly, he is fully aware of its existence and its crimes, and he works actively behind the scenes with Conan to plan countermeasures, even supplying specialized devices for high-risk operations such as the staged death of a key ally.

His key relationships reflect his role as a pillar of the main cast. With Conan and Shinichi, he is a trusted confidant and collaborator who keeps the most dangerous secret in the series. With Ai Haibara, he becomes a father-like guardian, offering her stability and acceptance after her escape from the organization. With the Detective Boys, he is a benevolent supervisor, a driver, a quiz master, and a protector. Ran Mōri regards him as a familiar friendly figure from her childhood, and Kōgorō Mōri treats him with respect. He also enjoys good relations with police officers such as Inspector Megure, and Shinichi's parents entrust him with the truth about their son. His romantic history includes Fusae Campbell-Kinoshita, his first love from elementary school, who remains emotionally significant to him.

Over the course of the series, Agasa develops from a comical inventor neighbor into an indispensable support figure. His inventions gain wider recognition, are praised by professionals, and are even used during official events, while his role as a stand-in speaker during some detective deductions leads the police to regard him as a capable investigator, usually with humorous results. His decision to shelter Haibara adds considerable depth to his character and provides her with a caring home, while his own first-love story reveals a sentimental side beneath his cheerful exterior. His laboratory has been damaged by his own experiments from time to time, and his house has required rebuilding, yet he remains an enduring source of warmth in a world filled with serious cases.

His most notable ability is his inventive genius. He creates the vast array of gadgets that allow Conan to operate effectively despite his childlike body, and many of these devices have been essential to solving cases and surviving dangerous encounters. He is highly intelligent, with advanced academic training and a broad base of technical knowledge, and he often assists Conan by researching information that a child would not be able to access on his own. He is also skilled at keeping secrets, remaining calm under pressure, and providing practical help at critical moments. His inventions occasionally fail or prove comically impractical, but his best work is reliable, innovative, and central to nearly every case Conan faces.