Suspect X

Suspect X (容疑者Xの献身, Yōgisha Ekkusu no Kenshin) is a 2008 Japanese mystery-thriller film based on the novel, The Devotion of Suspect X, directed by Hiroshi Nishitani. The film was a continuation of the popular Japanese serial drama Galileo and included the same cast. It topped Japan's box office for four consecutive weeks and was the third-highest grossing Japanese movie in 2008. The soundtrack was released on October 1, 2008.

Plot

A murder has occurred and the police are unable to find loopholes in the alibi of the main suspect, thus creating obstacles in the investigation.

Yasuko Hanaoka (Yasuko Matsuyuki) is a divorced, single mother who owns a restaurant. Tetsuya Ishigami (Shinichi Tsutsumi) is a reclusive, but brilliant mathematics teacher, who lives next door of Yasuko and Misato (Yasuko's daughter). Ishigami is solemn and introverted, and his morning exchanges with Yasuko from whose restaurant he buys lunch, is the brightest part of his day. When Togashi (Yasuko's abusive ex-husband) shows up one night to extort money from Yasuko, threatening both her and her teenaged daughter Misato, the situation quickly escalates into violence and Togashi is killed by mother and daughter on the apartment floor. Overhearing the commotion from his room and deducing that Togashi has been killed, Ishigami offers his help to the mother and daughter. He not only disposes the body, but also plots the cover-up step-by-step.