The students observing from the small classroom were all stunned.
They were taking a class on this very subject, and a case like this had happened right at the school. Naturally, they had their own theories.
So far, most of them considered Claude and Gonzalez the prime suspects. They had been the last two people to see Bonu, after all. They might not have been able to beat her head-on, but what if they had used some kind of trick?
Of course, some had thought more deeply. They had also settled on a killer in their minds and confidently believed Professor Schiller had reached the same conclusion.
First, there was their deduction.
The key to the Secret Chamber was how the killer had gotten in and how they had left.
For the Secret Chamber formed by the small classroom and the hallway, there seemed to be only one possible route inside.
The electrical room contained a great deal of equipment, creating blind spots in the surveillance coverage. Although those blind spots were not large enough to fit a person, someone could probably get through with a little ingenuity.
The killer could enter through the electrical room's window, get into the storage room, then slip out through its door while the elevator doors were closing and the camera could not see them. They could cross in front of the elevator doors and enter the small classroom opposite.
But there was one problem: there was no door between the electrical room and the storage room.
There was also no door between the large classroom and the small classroom. To enter the other classroom, one had to leave through this classroom's door, enter the hallway, and then open the other door.
Whether between the electrical room and storage room or between the large