There's a mysterious bomber in the city who leaves their calling card behind. In the scene of the crime, Neuro and Yako meet Usui, Sasazuka's "boss" who is skeptical of Yako's deduction ability. Despite of Usui's threats, Neuro and Yako take matters into their own hands and find out the pattern of the bomber of destroying buildings. As soon as they know the next building to be targeted, they go in and de-activate the bomb that was in the Women's bathroom, so as to lure the bomber. They are successful, and catch the criminal, a woman who reveals herself as being "Histerrier," and that she bombed buildings due to the frustation of not being able to be herself around her family. After de-activating a second bomb with Sasazuka's help, Neuro eats the mystery and "Histerrier" is arrested. However, towards the end of the episode, Yako is told that the way Sasazuka stopped the bomb (shooting it with perfect accuracy) was a method not taught by the police. (thetvdb.com)