Psychological Research Lab Murder Case

The **Psychological Research Lab Murder Case** is a murder case that occurred at the Maruyama Laboratory in Tokyo University.

It is the 13th main case in the *Ron Kamonohashi: Deranged Detective* series.

## Overview

Ron and Toto accompany Chicory to Tokyo University because she has to gather data about Professor Maruyama's cognitive psychological research laboratory. There, they meet Takanori Aoe who is in charge of the laboratory because Maruyama is attending a conference in America and the students Kanae Himeno, Riko Niki, Shun Oigawa, and Renjiro Imai. Tensions are high in the lab. The next morning, Himeno dies in an explosion in the lab.

The shield room was filled with flammable gas. Himeno opened the door, the gas touched an external heat source, presumably a heat gun, and exploded. Because flammable gas is never used in the experiment room and a heat gun would have never been left out, Himeno's death is treated as a homicide. In the explosion, a computer containing ten years' worth of experiment data was destroyed.

Furthermore, the lab received a threat letter addressed to Himeno this morning; it was sent out yesterday. Thus, only someone who knew Himeno would be in the experiment room this morning is the culprit.

The night before, Aoe performed an experiment with the MRI machine in the research wing. Oigawa, Niki, and Imai all knew that Himeno would use the experiment room this morning because they all wanted to use the room at that time and did a lottery to determine who would get the slot. The three of them woke up around nine and then went to the university; before that, they were just sleeping at home. All of them did not like Himeno for various reasons.

## History

Toto visits Ron, and when he sees him playing with dinosaurs, he misinterprets the situation and assumes Ron has regressed out of boredom and advises him to see Mofu. Ron explains that he is recreating his memories because his memories before the age of six are spotty, e.g., although he can clearly remember certain events like playing dinosaurs with Max and Molly at 11 a.m. on April 11th when he was three years old, he cannot remember the fourth person who was with them. Through the reenactment he hopes to remember that person, but his attempts have been in vain so far.

Ron is actually bored though, only Toto has no case for him; after all, he is a police officer and not a reporter like Chicory who actively looks for cases. This prompts Ron to contact Chicory to get a case.

The next day, Ron and Totomaru meet Chicory at Tokyo University. Chicory is very happy that she can gather data with the Metropolitan Police Department's "ace" but displeased to see Ron with Toto. However, her mood quickly changes when he tells her that he now wants to become a detective like Toto; she gives him her full support, and they head to the research lab.

In the Maruyama Laboratory, they are welcomed by Takanori Aoe who briefly tells them what they do—researching the mechanisms of emotions and learning—, and Ron asks if he knows why his early childhood memories are missing pieces. Aoe replies that there are multiple possible causes, e.g. dissociative amnesia; powerful shocks can delete memories from around the event. Then, Aoe has to leave because he has to attend a meeting. In his stead, Kanae Himeno will continue the tour. Himeno informs Ron, Chicory, and Toto about Aoe's extraordinary accomplishments in the field of memory research. She greatly idolizes him, and she and Chicory bond over their admirations for someone—Aoe for Himeno, Toto for Chicory.

After Himeno shows Chicory, Totomaru, and Ron the shield room, Shun Oigawa and Renjiro Imai, get into a fight about using the experiment room in the afternoon. Riko Niki then asks Himeno why she does not "flirt" with Aoe so that he can solve the problem as this is what she "always" does. Later, when it is time for Totomaru, Ron, and Chicory to leave, Himeno apologizes for this incident. Toto replies that it is fine; everyone gets stressed out sometimes after all. Ron adds that he can understand as the competition at the school he attended was fierce as well. People often started fights with him; he would then end them by breaking the other's nose. The anecdote lifts Himeno's mood and she swears to work hard to benefit humanity with her research like Professor Aoe does.

The next morning, Ron and Toto are at Pot Coffee when Toto receives a call from Chicory: Himeno was killed in an explosion at the research lab.

Toto and Ron head to Tokyo University, and Toto goes to speak to Amamiya who is investigating the case. He informs her that he knew Himeno, and Amamiya tells him what the forensic analysis found out. Totomaru requests to be assigned to the case. Although Amamiya says that he should not bring personal emotions to work as this may affect the investigation, she fakes to have received a call about something "urgent" that requires her attention and leaves the case to Toto.

Afterward, Toto calls Chicory to inform her that he was given the case, and Chicory says she will join him at the university. He ends the call and goes to start the interviews with Ron. They speak to Aoe first who expresses his sorrow over Himeno's death and testifies that he performed an experiment with the MRI machine in the research wing last night. On the way out, he passed by the experiment room, but the light was out. He also tells them that they have to replace all equipment, among them a computer containing ten years' worth of experiment data, now and that the lab received a threat letter addressed to Himeno this morning; it was sent out yesterday. Thus, it seems that whoever knew Himeno would be in the experiment room this morning is the culprit. Ron and Totomaru proceed to interview Imai, Niki, and Oigawa.

The students reveal that they all knew that Himeno would be in the experiment room, and neither Imai nor Oigawa or Niki have an alibi as they all went to sleep early, woke up around nine a.m., and then went to university. To divert suspicion from themselves, they spill one another's reasons why they disliked Himeno: Himeno reported Oigawa to the university after he deleted other people's data off the computer, broke up with Imai, and scolded Niki for cancelling a MRI experiment. Because the MRI machine has a high maintenance cost, they have to keep the operation ratio high and are not permitted to cancel experiments.

Ron suddenly leaves the room, telling Toto to get the records of the experiment room's use log. Totomaru gets the use log and hurries after Ron. He wants to know why he was in such a haste, and Ron replies he had a bad feeling and wonders why the threat letter arrived *after* Himeno's death. After all, a threat letter loses its meaning if its target is dead. Totomaru remarks how well Ron can understand the criminal's thinking, and Ron says people have told him that all his life.

He adds that he also wonders how the culprit was able to mail the threat letter before it was even decided that Himeno would get the experiment room. Ron also inquires about the use logs, and Toto hands them to him. After reading through them, Ron solves the case.

They gather Aoe, Niki, Oigawa, Imai as well as Chicory, who has also come in the meantime, in a lecture hall to reveal what actually happened: Aoe is the culprit. He wanted to destroy the computer in the research lab as it contained evidence that he forges data for his academic papers. He erased the evidence with the magnetism of the MRI machine, and to divert the attention from the computer, he filled the shield room with flammable gas so that one of his students would trigger an explosion and die if they opened its door. As he could not know who would ultimately use the experiment room, Aoe sent threat letters addressed to each of his students. After learning that the explosion killed Himeno, he picked out the letter meant for her and showed it to Ron and Totomaru.

When Aoe asks how they found out that he is the killer, Ron says that he did not use the experiment room all week. Aoe highly values efficiency and, thus, did not use the room because he knew that it would be destroyed soon. The professor confirms this and says that he got so far by being thoroughly efficient. Chicory wants to know if he even feels anything about killing Himeno to protect himself. Aoe states that he does not feel bad he killed Himeno as he believes that some sacrifices are required to create a "great man." This disgusts Ron, but because he has taken his medication, he does not pressure Aoe to death, though he still tells him that he has no right to live in this world. Aoe then tries to blow them all up with a bomb, but Ron can tackle him down beforehand. He tells him that he cannot die because he has to spend his life atoning for Himeno before the medication's side effects make him lose his consciousness.

The next day, Totomaru attends Himeno's funeral before he visits Ron in the evening. Ron wakes up and tells him that he dreamed of his childhood again and is sure that there is something important in his past that he cannot remember. Totomaru replies that he cannot remember much from when he was little; he only remembers looking at his pet hamster's back. Ron remarks that this happens when one is raised looking at a hamster's back—much to Totomaru's confusion.

## References

1. ↑ *Ron Kamonohashi: Deranged Detective* manga; Chapter 35, pages 5-18
2. ↑ *Ron Kamonohashi: Deranged Detective* manga; Chapter 36, pages 2-3
3. ↑ *Ron Kamonohashi: Deranged Detective* manga; Chapter 36, page 8
4. ↑ *Ron Kamonohashi: Deranged Detective* manga; Chapter 36, pages 9-10
5. ↑ *Ron Kamonohashi: Deranged Detective* manga; Chapter 36, page 7
6. ↑ *Ron Kamonohashi: Deranged Detective* manga; Chapter 36, pages 10-15
7. ↑ *Ron Kamonohashi: Deranged Detective* manga; Chapter 35, pages 2-18
8. ↑ *Ron Kamonohashi: Deranged Detective* manga; Chapter 36, pages 2-19
9. ↑ *Ron Kamonohashi: Deranged Detective* manga; Chapter 37, pages 2-18