“Killing someone isn't like a long-distance run or riding a bicycle; there's no concept of conserving energy. Unless the murderer is a seasoned, experienced professional assassin who can precisely control the force of their attacks and is fully prepared for all sorts of reactions from the target… otherwise, the perpetrator would definitely go all out, using maximum force to tighten the wire around the target's neck until the victim completely loses the ability to resist.” Feng Bujue explained, “In that case, the murderer's hands would inevitably have some cuts or bruises.” He gestured with his own hand, “The injured area should be roughly on the edge of the palm, below the base of the little finger. Even if the steel wire is wrapped around the hand several times beforehand to increase the hand's bearing surface, most of the force will still be borne by this area during the actual act of murder.”

“Doesn’t that mean the case is practically solved?” Schofield said excitedly, “Forget about the locked room! Dumpty, go gather everyone in this villa right away and check their hands…”

“Hold on a minute, Detective,” Feng Bujue interrupted weakly. “Don’t forget the premise I mentioned… ‘if they didn’t take protective measures.’” He shrugged. “As long as the murderer wore a pair of slightly thick gloves, that problem would be solved. Moreover, if those gloves were long enough, the probability of their hands and forearms being scratched by the deceased would also be greatly reduced.”

This cold water instantly extinguished the excited glimmers in Schofield and Dumpty's eyes.

“But your idea is correct,” Feng Bujue said. “The inspection should still be done, but we have to be clear that even if there are no injuries on someone's hands, it doesn't necessarily prove that they are not the murderer.” He added, “Also, as you've seen, the deceased bled a lot, and his own hands were covered in blood. If the murderer didn't wear gloves, their hands would very likely have a lot of bloodstains on them, and they would leave bloody fingerprints everywhere when they escaped. Of course… although I think this is unlikely… we can't rule out the possibility that the murderer went to the bathroom to wash their hands before fleeing.”

Schofield nodded. “Okay… so, in addition to the murder weapon, what we need to pay attention to now is a pair of blood-stained gloves.”

“You won't be able to find them,” Feng Bujue delivered another bad news.

“Huh? What did you say?” Schofield asked doubtfully.

Feng Bujue replied directly, “After the murderer killed the person and arranged the room to be a locked room mystery, their location was outside the window… that is, outside the villa. They only need to walk a short distance and throw the murder weapon and gloves into the valley… who could find them?”

“Uh…” Schofield didn't dare to respond anymore. As soon as this great detective opened his mouth, he could point out a clue, but in less than two sentences, he would cut it off again.

At this time, Feng Bujue had turned and walked towards the door, “When I investigated the crime scene before, I checked very carefully… apart from the area around the corpse, the only bloodstain I could find was that extremely faint blood mark on the windowsill. Therefore… my speculation is as follows…” As he spoke, he had already arrived at the door of the guest room, locked it smoothly, and continued, “After the murderer killed the person, they first wiped the murder weapon, cleaning the blood on the wire as much as possible, and put it aside for later use. Then, they took off their gloves, turned them inside out and crumpled them into a ball, and also put them aside for the time being. Then, the murderer came over and locked the door. Of course, I think there's a 70% or higher chance that the door was already locked when the murderer killed the person.”

As he spoke, Jue Ge turned back and walked towards the window, “After confirming that the door was locked from the inside, the murderer took the gloves and came to the window, tying the steel wire to the window.”

Suddenly, Feng Bujue stopped in front of the window, looking embarrassed, “Uh… officers, which of you knows how to tie a slipknot?”

This guy's weakness in weaving was exposed again… although it didn't matter much.

“Um… what kind of slipknot do you need?” Dumpty walked over and asked.

“What… are there actually many ways to do it…” Feng Bujue's expression was unusually wooden, because the conversation had entered a realm that was like a blind spot for him…

“Yeah.” Dumpty scratched his head under his police hat. “My uncle is a sailor, and he taught me many kinds when I was a kid, like a clove hitch, fisherman's knot, sheepshank, sheet bend, figure-eight knot…”

At this moment, Jue Ge looked at the other person as if to say—"So you are the legendary ultra-high school knot-tyer who has already broken through the art of tying shoelaces."

“Anyway…” Feng Bujue simply changed the subject, “Listen to me, and you should know what kind of knot it is.”

The windows of this guest room were traditional casement windows, with a rake-shaped latch in the middle of each of the left and right window leaves. Feng Bujue pointed to the handle of one of the latches and said, “The murderer tied one end of the steel wire to this handle. Then they climbed out of the house, first closed the other window, and fastened the latch. Then, keeping the latch of this window in a horizontal state, they slowly closed it from the outside.”

“Oh! I understand.” Hearing this, Dumpty already understood what Feng Bujue meant. He took the piano string from Jue Ge's hand and quickly tied it to the handle of the latch. Then, he quickly climbed out of the window, holding the other end of the steel wire in one hand and slowly closing the window with the other. Then, he pulled the steel wire outward from the window gap.

“Yes, that's it…” Feng Bujue said to Schofield beside him, “You see, the position of the wire must be stuck in the gap at the bottom edge of the window, so that when the murderer pulls the wire, the latch will turn downward until it is fastened.”

Seeing this, Schofield also understood, “When the latch is fastened, it is in a vertical state. If you continue to pull, the loop of the steel wire will fall off the end of the latch handle. At this time, the slipknot will come loose, so in the end, you just need to pull the wire out.” He pointed to the windowsill, “In this process, due to friction, the wire leaves blood marks on the windowsill.”

“Yes, although the murderer has wiped the blood on the murder weapon to avoid exposing this design, it is still difficult to leave no trace at all,” Feng Bujue continued, “Generally, after killing someone, people will want to leave the scene as soon as possible.” As he spoke, Jue Ge opened the window, pulled Dumpty, and helped him climb back into the room, “Although the murderer in this case had a plan in advance, their mentality won't be too different from ordinary people when they actually implement it.”

Feng Bujue left the window and paced around the room, saying, “If they had prepared another steel wire specifically for setting up the scene, or had carefully washed the murder weapon with water in the bathroom after the murder… then the difficulty of us solving this locked room mystery might have been even higher.”

“Usually no one would go to that extent, right…” Schofield replied.

“Heh…” Feng Bujue smiled, a meaningful smile that made the two police officers feel chills down their spines.

“Okay, the basic method of murder is clear.” Jue Ge stretched and winked towards the door, “Next… let’s go talk to the suspects in this case.”