A man’s body is found in the suburbs of Tokyo. The dead man was hit by a car and his head beaten by the reckless driver after the accident. The dead man had a wife named Noriko. She likes fancy things and she has a lover named Tsukada. It's also learned that the dead man was insured for 300 million yen. The media and the public look at Noriko and her boyfriend Tsukada with suspicion, but they have perfect alibis. Then, Detective Hibiki, who is in charge of the case, and Private Detective Kono become involved in a series of mysterious murder cases.
Hiroshi Hamano, a professor at a medical university, is found dead. Going by the results of the autopsy, it appears he committed suicide by jumping off a roof, but going by eyewitness testimony and physical evidence at the scene, Detective Kamei suspects murder. A ticket for a train trip around Japan is found in the professor's pocket. However, nobody then could have known the shocking truth hidden behind the tour the dead man was supposed to attend...
