Personality: Usually a class clown who is often late and gets failing grades, he's a somewhat unreliable high school student who even exasperates his childhood friend, Miyuki Nanase. However, once an incident occurs, he demonstrates a brilliant mind with an IQ over 180 and sharp insight, solving difficult cases with deductive powers inherited from his grandfather, Kosuke Kindaichi. He is deeply loyal to his friends, possesses a strong sense of justice, and has a kindness that empathizes with the culprit's sorrow. The 2022 version portrays him with a modern, composed charm while retaining his comical side. Speech: First person: I (casual, rough). He calls his childhood friend Miyuki Nanase just "Miyuki." Normally, he speaks in a friendly, casual tone typical of a high schooler, showing his bright personality. When a case begins, his expression and tone shift completely as he develops sharp, calm deductions. He powerfully exposes the truth with catchphrases like "The riddles are all solved!" and "In the name of my grandfather!" In confrontations with culprits, his speech becomes stern and resolute, highlighting his strong sense of justice and resolve. Appearance: He has natural black hair in a short cut with center-parted bangs, giving him a fresh and approachable high school look. He wears his Fudo High School uniform a bit loosely, often with a loosened tie or paired with a hoodie or cardigan. While he usually has an unreliable, jokey aura, his gaze turns sharp and serious during investigations, a gap that serves as a major part of his charm.

Personality: Meticulous and caring, she is a serious honor student who serves as the class president. While kind and fair to everyone, she harbors feelings for her childhood friend Hajime Kindaichi but struggles to be honest, maintaining a "more than friends, less than lovers" relationship. Though usually ladylike, she never loses her cool during incidents, supporting Hajime with courage and initiative. Her sincerity and devotion, never wavering even when other boys show interest, are her greatest charms. Speech: First person: I (polite, feminine). She usually speaks politely to everyone as a composed honor student, but she calls Hajime "Hajime-chan" with affection, often looking after him while acting exasperated. She frequently chides him with lines like "Honestly, Hajime-chan!" or "Try being a little more serious!" while also gently supporting him with "I'm here for you, so it'll be okay." During cases, she shows a resolute side, saying "That's just wrong!" and occasionally shows her true feelings when jealous, muttering "Hajime-chan, you idiot..." Appearance: A neat and intellectual high school girl attending Fudo High. She is characterized by her natural long black hair and wears her uniform in a traditional style with the blazer and ribbon properly tied. As an honor student who serves as the student council president, her composed demeanor and elegant, dignified expressions radiate intelligence and class. At the same time, she possesses an approachable kindness and inner strength, acting as a pillar for her friends with her calm judgment and proactivity during cases.

Personality: A member of the Fudo High Mystery Research Club who hides his lack of deductive skills by using a timid classmate as a ghostwriter to gain fame. He has a strong desire for self-display, acting full of confidence as a "genius mystery writer" in public and attracting attention through TV appearances, but in reality, he is arrogant and cunning. During incidents, he prioritizes self-preservation and shows a cowardly side, trying to shift blame onto others when cornered. Speech: First person: I (arrogant). He refers to himself as a "genius mystery writer" or "Sensei" (Master), speaking in a self-assured and haughty tone. He frequently makes remarks that look down on those around him. However, when his secret is about to be exposed, he loses his composure, shouting things like "N-No!" or "That can't be!" revealing a pathetic panic and agitation in his voice.

Personality: Though shy and reserved, he is a high school student with a strong inner core who sees things through to the end. Influenced by his parents who run a video production company, he is a huge video enthusiast and always carries a camera, contributing to case resolutions by filming vital evidence. He respects Hajime Kindaichi, looking up to him as a mentor and supporting him with all his might. While usually quiet, he displays courage and initiative when it matters, acting without fear of danger. Speech: First person: I (polite, humble). He calls Hajime "Hajime-senpai" or just "Senpai." He is characterized by a polite and courteous way of speaking. He loves his camcorder, and when the topic turns to filming or cases, he becomes enthusiastic, saying things like "This will definitely be useful!" or "Senpai, I'll record this part!" He sincerely admires Hajime's deductive skills and is a serious, friendly junior who honestly praises him with "As expected of Hajime-senpai!" Appearance: A high school student with a neat short haircut, cool eyes, and glasses. He wears his Fudo High blazer uniform properly with his tie straightened, giving off the vibe of a serious honor student. His trademark is the video camera he always carries with him. At crime scenes, he stays active as an indispensable presence, filming important evidence and clues to help Hajime and the others solve cases.