"You guys stand back," Qian Yu took the hook part of the Traceless Umbrella (when Yiyu Lou, it was used for abseiling, remember?) Reach through the hole and try to pull up from the floor tiles where the small hole is.

As the floor tiles were pulled up, a secret passage appeared in front of them. The stench of the corpse almost made Chiba retch, and Yuan Tai behind him was even directly smoked by the pungent smell and wanted to vomit.

"Go to the grass and vomit!" Qian Yu hurriedly ordered-if he was allowed to spit it out here, once the owner of this secret passage came here, he would definitely suspect that someone had broken in.

A minute later, Motota walked back with a prostrated expression, and the others were somewhat accustomed to the smell.

"It's a stone-colored wooden door... Conan tried to shake the floor tiles after Chiba retracted the umbrella, and found that the weight and feel were subtle.

"I'll take the lead," Qian Yu glanced at the pitch black below. "After Conan, the others are between the two of us."

However, before he could go down, Qian Yu, who just put his face close to the entrance of the cave, felt that he couldn't breathe at all, and hurriedly stayed away from the hole.

"What the hell is this place—" Chiba grumbled, gulping for air. It's all the smell of carbon dioxide! ”

"Is there any creature in there that is suffocating to death?" Conan frowned. Can the flashlight shine underneath? ”

"Where's the flashlight?" Yuan was too confused.

"Didn't you bring it?" Taking out a flashlight, Chiba shone the light below the hole.

Beneath the entrance to the cave is an underground chamber, and on the ground of the chamber lies a highly decomposed corpse lying flat on the ground. It is noteworthy that the hands of the corpse were pressed against the chest and the legs were curled.

"Looks like that," Conan came to Chiha's side, glanced down, and immediately reacted. "This is the suffocating master."

"Long hair, adult body decay, presumably female, dead for a while."

"The soft tissues of the corpse began to erode, and the time of death was more than 13 days. Considering that this is an anaerobic environment, the rate of decay is slowed by 50 to 60 percent, and the time of death of the deceased is about 30 to 35 days ago. Conan said, closing the wooden door again. April 5th to 10th—"

Conan's expression suddenly became very strange, and his words began to be slurred.

"Is there anything wrong?" Chiba keenly spotted Conan's anomaly.

"No... It's nothing..."A cold sweat was already breaking out on Conan's head. "Let's go call the police, and then we'll go to the school building."

"Okay, we-" Chiba was interrupted in the middle of speaking.

"Smack!" There was a heavy sound of windows shutting in the school building - someone was inside the school building!

Chiba and Conan glanced at each other, both fearful of the unknown in their eyes.

"Wait a minute," Conan said, closing his eyes and taking a deep breath. If it was a corpse from a month ago, then the person who was in the school building now was most likely not the murderer. Moreover, if it is a death from suffocation, it may not have been a human killing. After all, this method of death is neither reliable nor quick-acting, and normal people would never kill people in this way. ”

"Maybe the murderer wasn't strong enough to subdue this woman? Lack of strength or disability? Chiba suggested a possibility.

"There are too many in elementary school that meet this condition... Conan pouted. "The principal, grandfather and other old men all meet this condition, and the female teachers also meet this condition. Even if you admit death, all the students are within the range of suspects. ”

"How many people know this place?" Qian Yu glanced in the direction of the secret room. "Since it was built here, it means that it must have been built when the construction of this site was just completed. But teachers will rotate, and there are too few people who worked in Didan when the school was established - the principal, the director of teaching, and the number of teachers who rotate back individually should be in single digits. ”

"Get them out of school first," Conan decided. "Then the two of us went and had a look."

"Why—oh..." Yuan Tai was about to exercise his right to free movement, but in the silent gaze of Qian Yu, he still chose to shut up - Qian Yu had reiterated many times before that only he and Conan had the right to act, and Yuan Tai couldn't say anything about him, so he could only reluctantly choose to listen to Qian Yu's words, at least on the surface.

。。。

"The door is locked..." Qian Yu looked at the school gate in front of him and said helplessly.

"Uncle the doorman, who is always useless at this critical time, is really... Conan pouted.

"What then?" Qian Yu asked with a frown. "I'm not going to pick the lock anyway, and I'll get in trouble if I force my way down. The school's isolation design is disgusting, with a six-meter-high gate and a four-meter-high fence that is impossible to climb. ”

“。。。” Conan thought for a moment and gestured to a nearby building. "Take them to places where they shouldn't be able to meet intruders."

"Physical Education Department?" Thousand Feathers were surprised. "I know the door to the PE department is broken, so I can go in. But are you sure you won't meet people? ”

"Seniors who were here 30 years ago generally have their own offices, after all, as long as they are not retired, they are big or small managers." Conan shrugged. "But you also know the situation of the physical education teacher, who eats young, so he definitely doesn't have old qualifications. If the murderer had his own office, why did he come to the Department of Physical Education? ”

"Ding ding—" A sudden sound appeared on Qian Yu's body.

"What sound? Cell phone? Conan wondered.

"If it's a mobile phone," Thousand Feathers rolled her eyes. "I would have called the police a long time ago! It's a sensor. ”

As he spoke, Qian Yu took out a box from his backpack, and a signal light board was installed in the plastic case on one side of the box.

"Someone has come out of the manager's office area," Qian Yu explained, watching a light come on. "But I don't know who it is, there is a lock in the manager's office area, and I can't get in."

"Anyway, it's not good... Conan was speechless. "I'm still here at this time, and I've probably been working at Didan for 30 years... We're probably going to meet the people we're looking for. ”

"Upstairs," Qian Yu walked towards the physical education department with three little ones who had no combat power, reading as he spoke. "Looks like it's going to the fifth or sixth floor."

"Good news," Conan shrugged. "He couldn't escape from the top floor anyway."

。。。

After placing the three little ones in the physical education department, Conan found that Qianyu's face had become extremely bad. "Is something wrong?"

"Either it's my eyes hallucinating, or it's hell." Chiba turned the signal light board he had been looking at to Conan.

The small sensor light at the staircase on the sixth floor turned on, but just a second later, the small sensor light at the staircase on the third floor came on. A few seconds later, the small sensor light at the entrance of Class A of the sixth grade turned on, and two seconds later, the small sensor light at the door of Class A of the third grade actually lit up.

"No... You have no vision, and we have not seen hell ... Despite that, Conan did have a "live hell" expression on his face.

"We met two uninvited guests...