Yoshitaro Nomura’s 1974 film of Seicho Matsumoto’s immensely popular detective story tells the tale of two detectives, Imanishi (Tetsuro Tamba) and Yoshimura (Kensaku Morita), tasked with tracking down the murderer of an old man, found bludgeoned to death in a rail yard. When the identity of the old man can't be determined, the investigation focuses on the only other clue: a scrap of conversation overheard at a bar between the old man and a younger one. A witness recalls the cryptic phrases "Kameda did this" and "Kameda doesn't change."