"Trickster" is a 24-episode anime series based on Edogawa Rampo's "The Boy Detectives Club" novels, blending mystery, science fiction, and supernatural elements. The story centers around Kensuke Hanasaki, a high school student and leader of the Hanasaki Detective Agency, a group of young detectives solving local mysteries. Their lives take a dramatic turn when they encounter Yoshio Kobayashi, a mysterious boy cursed with immortality due to an alien organism called the "Fiend with Twenty Faces." This organism renders Kobayashi unable to die, even by his own hand, leaving him in a perpetual state of despair.

Kobayashi's condition attracts the attention of the elusive criminal organization known as the "Twenty Faces," which seeks to exploit his immortality for their own purposes. The Hanasaki Detective Agency becomes entangled in the conflict, with Kensuke determined to uncover the truth behind Kobayashi's curse and the Twenty Faces organization. As the story progresses, the detectives uncover deeper layers of intrigue, including the origins of the Fiend with Twenty Faces, the true motives of the Twenty Faces organization, and the connections between Kobayashi and the group's enigmatic leader.

The narrative explores themes of identity, mortality, and the search for purpose, as Kobayashi struggles with his cursed existence and Kensuke grapples with his desire to protect others while confronting his own limitations. Supporting characters, such as the resourceful Akechi and the enigmatic Inoue, add depth to the story, each contributing their unique skills and perspectives to the unfolding mystery. The series balances episodic detective cases with an overarching plot, gradually revealing the larger conspiracy at play.

As the detectives delve deeper into the mystery, they face moral dilemmas, unexpected betrayals, and the realization that the line between good and evil is often blurred. The story builds toward a climactic confrontation with the Twenty Faces organization, culminating in a resolution that ties together the personal struggles of the characters with the broader narrative. "Trickster" combines a classic detective framework with speculative elements, creating a story that is both grounded in its character-driven drama and elevated by its supernatural and sci-fi undertones.