Suspect X

An evening confrontation in Yasuko Hanaoka's apartment ends in tragedy when Togashi is killed in the struggle. Yasuko and her daughter Misato decide to cover up the murder rather than risk exposure or retaliation. The apartment is left with a chilling silence as they attempt to erase the evidence.

Ishigami, a reclusive mathematics teacher living next door, overhears the violent scuffle and quickly realizes what happened. He offers his help to Yasuko and Misato, presenting himself as a capable ally who can manage the situation. He begins to consider disposing of the body and laying out a cover-up plan.

Ishigami takes on the meticulous task of disposing the body and guiding the cover-up, moving pieces of evidence and orchestrating alibis. He uses his logical mind to map out a flawless sequence of events and misdirections. Yasuko and Misato come to rely on their unlikely ally to shield them from detection.

The corpse is found and identified by investigators, immediately placing Yasuko at the center of the investigation. Detectives Utsumi and Kusanagi vow to pursue every lead while treating Yasuko as a prime suspect. The case shifts from a crime of passion to a carefully watched inquiry.

Detective Kaoru Utsumi and her superior Shunpei Kusanagi seek help from Manabu Yukawa, a renowned professor whose expertise lies in physics. Yukawa initially refuses to assist, arguing that the case does not fall within his field. When he learns Ishigami is Yasuko's neighbor, he reconsiders and agrees to take a closer look.

Yukawa's stance softens after the discovery that Ishigami is the neighbor. He agrees to help and begins to explore the case more deeply. This decision sets the stage for an intricate investigation that blends science with human psychology.

Yukawa meets Ishigami and is struck by the man's sharp intellect and calm demeanor. The reunion plants seeds of doubt about Yasuko's guilt and spurs Yukawa to pursue the case with renewed vigor. He decides to investigate further to test the boundaries of the suspect's alibi.

A tense intellectual duel unfolds as Ishigami defends Yasuko and Yukawa tries to reconstruct events using physics and timing. Yukawa tests alibis and timelines, seeking any inconsistency that could reveal the truth. The investigation deepens, pushing both men to their limits.

Yukawa pieces together the hidden contradictions and arrives at a conclusion that challenges Yasuko's narrative. He discerns a hidden truth about the crime that points to a deeper mastermind behind the cover-up. The deduction marks a pivotal turn in the investigation.

Yukawa informs the police of Ishigami's role, presenting a calculated and devastating revelation. The perfect crime narrative collapses as the human cost of the deception becomes clear. The revelation realigns the entire case toward Ishigami.

The truth brings no real gain for Yasuko or Ishigami, though it helps the police close the case. Yasuko's life is left in turmoil, while Ishigami bears the burden of his actions. Yukawa, typically detached, is visibly distraught by the emotional and moral fallout.

In the aftermath, Yukawa contemplates the limits of logic and the human cost of solving crimes. He remains dedicated to his work, yet the case leaves a lasting mark on him, a reminder that some truths cut deeply. The investigation closes, but the emotional wounds linger.