A serial bomber named "Histerrier" is bombing buildings and landmarks. At a crime scene, Neuro and Yako meet Usui, Sasazuka's boss, who doubts Yako's deductive ability. Despite Usui's threats Neuro and Yako discover the next targeted building, deactivating the bomb to lure the bomber. They are successful, and the criminal is a woman known as Histerrier. After deactivating a second bomb with Sasazuka's help, Histerrier is arrested.