Shi no Hassou SP

Sokoi Takehachi and Tsumura Aki are journalists working for the "Weekly Dodongo". Their editor, Yamazaki Jiro, had assigned them to stake out former state assemblyman Okase Shohei, who is about to be released from prison. 7 years ago, Okase was found guilty of misappropriating state funds amounting to 100 mil yen. However, only 70 mil yen were accounted for during the trial. Yamazaki has a hunch that upon his release, Okase will be retrieving that money from wherever he had hidden it. Both Takehachi and Aki had tailed Okase to the racecourse, and from there to a street near Kagurazaka, Tokyo, where they lost him. Next thing they know, the news world is abuzz with the rumor that Okase had found the body of a strangled man at a cemetery in Katsuura, Chiba. Yamazaki's instinct tells him that the murder has something to do with the unaccounted for money, and so he decides to bring Takehachi along with him to call on Okase. They pay a visit to the Nishida Stables, where they are introduced to the stable hand, Suekichi Hideo, the stable owner, Nishida Ryuzo and one of the racehorse's owner, state assemblyman Tateyama Torahei. Yamazaki decides against bringing up the matter of Okase, which puzzles Takehachi, but yet Yamazaki does not share his reason for doing so with him. Not long after, a trunk is found in the forests of Mizusawa, Iwate. In it is a corpse of a man. How is the corpse related to Okase? Why was it stuffed inside the trunk?