The Third Dead Angle 1959

Yoshikawa and Kaji are alumni - Yoshikawa leads a life loyal to his company Toho Corporation, whilst Kaji works in the underground world for Aoyama, a fixer trying to buy Toho out. One day, Yoshikawa is ordered to take a look into the information leakage which had resulted in a serious fall of the company stock price. Following his order, Yoshikawa reunites with Kaji but their relationship gets complicated through the presence of Akiko, the daughter of Kubo, chairman of Toho Corporation. There is an obvious financial conspiracy and several men are killed - Who is the true mastermind behind all the plots?