In Conan, people have a brain option system

Everyone in the room looked in the direction of the sound.

Then I saw Moto Kojima who found a Masked Superman hood from somewhere, and even put the hood on his own head.

Putting on the Masked Superman hood, Kojima Genta seemed to have transformed into a Masked Superman, shouting excitedly.

"Hey, Mr. Yuantai, put it down quickly! This may be an important piece of evidence!"

Dr. Agasa was startled and hurriedly stepped forward to ask Genta Kojima to take off his headgear.

However, Dr. Agasa just came to Genta Kojima.

I saw Genta Kojima, who was wearing a Masked Superman headgear. His fat body looked like he was drunk. He staggered twice and fell to the ground.

"Genta!"

Conan and Haihara Ai shouted and rushed to Genta Kojima's side.

Haibara Ai pulled off the Masked Superman hood on Kojima Genta's head, and found that Kojima Genta was in a trance and looked completely weak.

She reached out and opened Kojima Genta's eyes, and saw that Kojima Genta's eyes were red and even crying.

“There’s hydrogen sulfide in this hood!”

Haibara Ai recognized at a glance that Motoda Kojima was suffering from hydrogen sulfide poisoning symptoms.

The detectives who heard Haiyuan's screams were also shocked.

A policeman quickly took the detector and put it inside Masked Superman's hood to test the concentration of hydrogen sulfide inside the hood.

The test result is [90ppm], which is 0.009%.

For hydrogen sulfide, this is a concentration sufficient to cause poisoning symptoms such as dizziness and nausea.

And because Moto Kojima was a child, this concentration of hydrogen sulfide also caused him to become comatose in a short period of time.

"Fortunately, the concentration of hydrogen sulfide is not too high. Yuantai probably inhaled too much in a short period of time and fell into coma."

Hui Yuarai breathed a sigh of relief and said softly.

Conan looked at the Masked Superman's hood and finally figured out one of the doubts in this case.

"According to our original idea, the murderer must have produced hydrogen sulfide gas in Furusawa Takeshi's room."

"But because the gas evaporates, it is very strange that there is no hydrogen sulfide gas in the air at the murder scene."

"However, if you are actually just killing one person, there is no need to produce a lot of hydrogen sulfide gas."

"The murderer only needs to make hydrogen sulfide gas in an airtight leather holster, then put the hood on Furuzawa Takeshi's head, and then block the ventilation holes to complete the murder with a small amount of hydrogen sulfide gas!"

"In this way, even if a little hydrogen sulfide gas is emitted, it will not have a big impact on the air in the room."

Conan immediately figured out the murderer's method of killing.

"Then, what's left is the murderer's method of producing hydrogen sulfide."

Although Moto Kojima only fell into a coma briefly, the detective still called an ambulance just in case.

At the same time, the police from the forensics department took away the Masked Superman hood used by the murderer to make hydrogen sulfide and serve as a container.

"Can you detect how hydrogen sulfide is produced?"

Conan asked Haihara Ai in a low voice.

"The ingredients before the reaction may be able to be found, but if you want to determine what specifically it comes from, it may take a long time."

Huihara Ai replied.

After Conan briefly exchanged opinions with Haibara Ai, he then went to check the rooms of Mayumi Motoki and Shoichi Matsutani.

Then it was discovered.

Shoichi Matsutani's suitcase was not that big, and there was a lot of luggage in it. It was obviously not enough to hide the black suitcase used for throwing corpses.

Motoki Mayumi has a rather large suitcase, which can fit into a small suitcase.

Originally, in the judgment of Conan and most of the detectives present, Mayumi Motoki, the first discoverer, was not very suspicious.

Because Mayumi Motoki is a woman who does not look strong, it is obviously not easy to complete the process of killing and dumping the body alone.

But after they heard Kyusuke Akikawa say that Mayumi Motoki and Shoichi Matsutani had privately discussed the killing of Takeshi Furuzawa,

I started to think about it as if Motoki Mayumi and Matsutani Shoichi cooperated to complete this murder.

In this way, Motoki Mayumi's suspicion is very high.

only.

After searching their rooms and luggage, the police also found no suspicious chemicals.

"Could it be that when the murderer threw away the suitcase, he also threw away the things used to make hydrogen sulfide?"

"Or maybe they just brought a dose that was just enough to react and used it all up when making hydrogen sulfide gas?"

The police officer from the Kanagawa Prefectural Police Headquarters asked Dr. Agasa.

"Even if it happens to run out, there must be a container to hold things containing hydrogen sulfide substances, and a container to hold the 'acid' used for the reaction."

"Besides, I don't think they can control the dosage so precisely."

Haihara Ai gave the answer.

So Conan followed Haibara Ai and once again carefully inspected the rooms of Mayumi Motoki and Shoichi Matsutani.

Then Conan discovered that the bathtub in Shoichi Matsutani's room showed signs of being used.

In Matsutani Jōichi's luggage, Conan also found some bathing agents that had been opened and used.

It is not uncommon for Japanese people to use bathing agents when taking a bath.

But the problem is that the bathing agents used by Matsutani Jōichi are sold by Kosen-an, their own brand of bathing agents.

The characteristic of this bathing agent is that it can perfectly restore the hot springs of Kosen-an.

This immediately aroused Conan's suspicion.

'He came to the hot spring hotel to check in, but Matsutani Jōichi still wanted to take a bath in the room. '

'Forget about taking a bath, the bathing agent he used is still Kosen-an's bathing agent. '

'In that case, why didn't he just go to the hot spring downstairs to take a bath? '

'No matter how you think about it, the real thing is much better than the fake hot spring made with bathing agents, right? '

'Unless, his purpose is not to take a bath at all, but to do other things with the bathing agent. '

Conan thought in his heart, so he hurriedly confirmed the ingredients of Kosen-an's bathing agent.

As expected, Conan soon found magnesium sulfide in the ingredient list of Kosen'an bathing agent.

Magnesium sulfide is used in bathing agents, usually to provide minerals and foam effects,

so as to better restore the feeling of natural hot springs.

"Haibara, this!"

"Yeah."

Ai Haibara stared at the ingredient list of Kosen'an bathing agent in her hand and nodded solemnly.