"Kindaichi Shōnen no Jikenbo: Kyūketsuki Densetsu Satsujin Jiken" is a two-episode anime OVA that adapts a story arc from the "Kindaichi Case Files" manga series. The narrative centers on Hajime Kindaichi, a high school student with a sharp intellect and a knack for solving complex mysteries, and his childhood friend Miyuki Nanase. The story unfolds during a school trip to the remote village of Yatsugatake, where the students encounter a chilling legend about a vampire that has haunted the village for centuries.

Upon arrival, the group learns of the "Vampire Legend Murder Case," a series of deaths tied to the vampire myth. The villagers believe the vampire is responsible for the murders, which occur every few decades. The students, including Hajime and Miyuki, stay at a local inn run by the eccentric Himura family, who are deeply connected to the legend. Strange occurrences begin almost immediately, with eerie sightings and unexplained events fueling the villagers' fears.

The tension escalates when one of the students is found dead under mysterious circumstances, bearing marks resembling vampire bites. Hajime, skeptical of the supernatural explanation, begins investigating the case, uncovering a web of secrets tied to the Himura family and the village's history. As more deaths occur, the villagers grow increasingly hostile, convinced the vampire is real. Hajime must unravel the truth behind the murders, which involve hidden motives, long-buried grudges, and a cleverly orchestrated plot designed to exploit the vampire legend.

The story delves into themes of superstition, human psychology, and the power of belief, as Hajime uses his deductive skills to challenge the supernatural narrative. The Himura family's dark past and their connection to the murders are gradually revealed, culminating in a confrontation that exposes the true culprit. The resolution hinges on Hajime's ability to piece together the clues and expose the human greed and malice masquerading as a supernatural curse.

The OVA maintains a suspenseful atmosphere, blending elements of mystery, horror, and detective fiction. Hajime Kindaichi's character is central to the narrative, with his sharp intellect and determination driving the investigation. Miyuki Nanase provides emotional support and serves as a grounding presence, while the Himura family and other villagers add layers of intrigue and suspicion. The story effectively balances its supernatural overtones with a grounded, logical resolution, staying true to the series' emphasis on solving crimes through reason and evidence.