"City Hunter The Movie: Angel Dust" centers on Ryo Saeba, a skilled private detective and marksman known for his sharp instincts and flirtatious personality. The narrative unfolds in modern-day Tokyo, where Ryo is approached by a mysterious woman named Kaori Makimura, who seeks his help in locating her missing sister, Yuri. Yuri, a scientist, has disappeared under suspicious circumstances linked to her research on a powerful new drug called Angel Dust. This drug, capable of enhancing human abilities to extraordinary levels, has attracted the attention of dangerous criminal organizations.

As Ryo investigates, he uncovers a conspiracy involving a shadowy pharmaceutical company and a secretive military group. The stakes escalate when it becomes clear that Angel Dust has lethal side effects, and its misuse could lead to catastrophic consequences. Ryo’s investigation leads him to cross paths with a former associate, Falcon, who has his own reasons for pursuing the drug. The two form an uneasy alliance, navigating a web of betrayal, high-stakes confrontations, and moral dilemmas.

Throughout the film, Ryo’s signature blend of humor, action, and sharp detective work drives the story forward. His interactions with Kaori reveal a deeper emotional layer, as her determination to save her sister mirrors Ryo’s own sense of justice. The narrative builds to a climactic showdown, where Ryo must confront the masterminds behind the Angel Dust operation and prevent the drug from falling into the wrong hands. The film balances intense action sequences with moments of character-driven drama, staying true to the spirit of the "City Hunter" franchise while expanding its scope with a high-stakes, cinematic storyline.