"Red Ash -Magicicada-" is a supernatural mystery anime that intertwines themes of folklore, tragedy, and human connection. The story is set in a rural Japanese village where a mysterious cicada, known as the Magicicada, emerges once every 13 years. This event coincides with a series of unsettling occurrences, including disappearances and deaths, which the villagers attribute to a curse tied to the cicada's arrival.

The protagonist, a high school student named Kōichi Sakakibara, moves to the village to live with his grandparents after his mother's death. He enrolls in a local school and quickly becomes entangled in the village's dark secrets. Kōichi befriends a group of classmates, including Mei Misaki, a quiet and enigmatic girl who is ostracized by her peers. Mei is central to the unfolding mystery, as she possesses a unique connection to the curse and the supernatural forces at play.

As Kōichi investigates the strange events, he uncovers a tragic history involving a series of deaths that occur every 13 years, coinciding with the Magicicada's emergence. The curse is linked to a past incident involving a group of children, including Mei, who were involved in a fatal accident. The survivors, now teenagers, are haunted by guilt and fear, believing they are destined to die as part of the curse's cycle.

The narrative explores the psychological toll of the curse on the characters, particularly Mei, who struggles with her identity and the burden of her past. Kōichi's determination to uncover the truth leads him to confront the villagers' superstitions and the deeper, more personal connections between the curse and the people affected by it. The story builds tension through its exploration of fate, memory, and the blurred line between reality and the supernatural.

The anime's pacing is deliberate, with a focus on atmospheric storytelling and character development. The mystery unfolds gradually, revealing layers of the curse and its impact on the village and its inhabitants. The resolution ties together the themes of loss, redemption, and the cyclical nature of tragedy, offering a poignant conclusion to the intertwined fates of the characters.