Detectives Takayama and Oshita participate in a major drug bust which arouses suspicion that the government may be secretly involved.

Toshiki Takayama (Taka) and Oshita Yuji, who had retired as detectives and opened a private detective agency in New Zealand, returned to Yokohama for the first time in 8 years. One day, a Japanese lawyer living in Hong Kong is murdered. Taka, who felt suspicious about the incident, visits Liu Fei Long, a man who has a connection with the two in the past, but Taka is worried that Stella Lee, a business partner of Fei Long, who he met there, looks like his former lover. At the same time, a young woman named Ayaka Nagamine visited the pair at the "T&Y detective agency", asking for help in finding her mother. Natsuko, Ayaka’s mother, was an old acquaintance of Taka and Yuji. The pair started searching for Natsuko, but there was a series of murders in Yokohama. Eventually, these escalate, and a terrorist plot involving a bomb is afoot.

Taka and Yuji find evidence in a 15-year-old case, but the statute of limitations expires in four days and they're hunting illicit gun manufacturers.

When a doctor is found dead and the company's exclusive data on a cancer drug is missing, detective Takayama and Oshita are called to the Nakamitsu pharmaceutical laboratory. However, a bungled attempt to catch the murderer leave Takayama and Oshita reassigned to the lackluster task of patrolling public bathrooms to keep them out of trouble.