Three incomprehensible serial murders occurred in Tokyo. There was no trace of the suspect, and the police could only deduce from the code left at the scene that the next crime scene would be at the Cortesia Hotel in Tokyo.
Kosuke Nitta, a young detective from the Investigation Section, disguised himself as a hotel employee and sneaked into the search. Cooperating with him was Naomi Yamagishi, the hotel's senior receptionist. Due to their differences in work philosophies, the two had constant conflicts. However, in the process of conflicts arising and resolving, the two gradually established a deep trust.
At the same time, they are getting closer to the truth step by step.
