The 29th Detective Conan film unfolds in the port city of Yokohama, which is bustling with activity as it hosts the Kanagawa Motorcycle Festival. Conan Edogawa, Ran Mouri, and Kogoro Mouri head to the event to meet up with the high school detective Masumi Sera. As they navigate the heavy traffic, they witness a high-speed chase unfold on the roads. A mysterious black motorcycle, weaving through cars at incredible speeds, is being pursued by a white police motorcycle ridden by Chihaya Hagiwara, a member of the Kanagawa Prefectural Police's traffic unit known as the Goddess of Wind. The chase ends in chaos when Chihaya's bike is destroyed, and the dark rider, later dubbed Lucifer, escapes.

Upon arriving at the festival, Conan and his friends watch the unveiling of a cutting-edge new white motorcycle prototype called Angel. However, the shadowy black bike soon reappears, easily evading all police units sent to intercept it. This criminal rider gains the nickname Lucifer because of its uncanny resemblance to the Angel prototype, sparking a mysterious and dangerous rivalry between the two machines. The investigation draws Conan into a high-velocity mystery, forcing him to question who the masked rider is and what their goals might be.

Central to the narrative is Chihaya Hagiwara, who is making her first appearance in a film. The case stirs painful memories for her, specifically related to her late younger brother, Kenji Hagiwara, a former member of the Tokyo Metropolitan Police Department's bomb squad who died in the line of duty, and his close friend and classmate from the police academy, Jinpei Matsuda. Inspector Jugo Yokomizo of the Kanagawa Police also plays a key role in the investigation, while Masumi Sera, who shares Chihaya's passion for motorcycles, actively assists Conan.

As Conan and Chihaya dig deeper, they uncover a conspiracy involving the developers of the Angel motorcycle. The inventor, Ohzeki Kazuaki, murdered his former partner, Sasaki Naoyuki, and staged it as an accident to cover up a scheme to illegally collect military application data. The case becomes further entangled with revenge as the black-clad Lucifer rider is revealed to be Asagi Ichika, a senior officer and friend of Chihaya who was injured in the accident that killed Sasaki, forcing her off motorcycles. Meanwhile, the bike's designer, Ryuri Kiriko, is revealed to be Sasaki's sister, plotting her own revenge against Ohzeki.

The climax erupts on the Yokohama Bay Bridge. After Ran is kidnapped, Conan and Chihaya engage in a life-threatening pursuit. Ohzeki unleashes a fleet of autonomous vehicles to block their path. Chihaya, momentarily doubting herself, is inspired when Inspector Yokomizo relays that her late brother Kenji and his friend Jinpei Matsuda believed she was invincible. Regaining her resolve, she rides the black motorcycle Lucifer up the main cable of the Bay Bridge, crashing into the helicopter from which Ryuri is orchestrating her revenge. Conan disables the remaining threats inside the helicopter using his soccer ball, and Chihaya successfully talks Ryuri down from her vengeance. No culprit dies, and the case is solved.