After some questioning, Xu Mo had almost dismissed his suspicions about the patient.
A patient with severe cognitive impairment, who believed he was a mushroom and would squat motionless in his room every night, was unlikely to be the murderer.
Xu Mo decided to interrogate another suspect: the security guard, Old Ding.
After the medical staff took the patient away, Xu Mo had the officers bring Old Ding over.
When Old Ding learned that the police wanted to question him, the honest and timid man immediately became nervous.
"Don't be nervous, sit down. We just want to ask you a few questions. Answer truthfully, and that's all," Xu Mo said with a smile, trying to ease Old Ding's tension before starting the interrogation.
"Okay... okay, Officer. Ask away," Old Ding replied, still somewhat uneasy.
"Where did you go after sunset yesterday?"
"I didn't go anywhere. I stayed in the security guard's duty room the whole time."
"You didn't even step out of the duty room?"
"No," Old Ding nodded, his tone firm.
With his expertise in psychology, Xu Mo could easily tell that Old Ding wasn't lying. After sunset yesterday, he truly hadn't gone anywhere.
This left Xu Mo puzzled.
If Old Ding hadn't gone anywhere after sunset, he couldn't be the murderer, as the victim's time of death was in the evening.
Could the murderer be the patient who had left earlier? Was it possible that the patient wasn't, as the medical staff had said, squatting motionless in his room at night?
But that didn't make sense either. The medical staff showed no signs of lying, and she had no reason to cover for a mentally ill patient.
A mentally ill patient might not necessarily go to jail for murder, but anyone who covered for them would definitely face imprisonment. It wasn't worth it, and it didn't add up.
Xu Mo's brows furrowed slightly.
If the murderer wasn't the patient or Old Ding... had the investigation taken a wrong turn again?
If that were the case, this case was going to be quite troublesome.
Seeing that Xu Mo wasn't making much progress, Han Fei decided to gather all the officers and conduct a thorough search of the psychiatric hospital. He wanted to find the murder weapon and the victim's torso, hoping to extract some clues that could assist in solving the case.
Earlier, Han Fei hadn't ordered the officers to search for the weapon and the body immediately upon arrival because he believed that the killer's handwriting alone would be enough to catch the culprit. He thought it unnecessary to expend a lot of manpower and time searching for the body and the weapon, as they could always find out where the killer had hidden them after capturing him. In his view, spending too much effort on searching for the body and weapon first was putting the cart before the horse.
But now, Han Fei had changed his mind.
Taking shortcuts wasn't working... they had to follow the proper procedures.
"Everyone, gather around," Han Fei waved to the officers, preparing to instruct them to conduct a thorough search of the psychiatric hospital.
Hearing this, Xu Mo glanced at Han Fei's location, then turned to Old Ding and said, "I'm done questioning you for now. You can go back, but I might need to speak with you again if any issues arise."
Old Ding acknowledged and turned to leave.
Xu Mo then walked over to Han Fei.
"I think we should conduct a thorough search of the place first. We need to find the body and the weapon—it might help with the investigation," Han Fei said, then looked at Xu Mo. "Captain Xu, do you have any good ideas?"
Xu Mo shook his head, indicating that he was also at a loss.
"Let's proceed as you suggested."
...
Under Han Fei's direction, the officers dispersed and began a thorough search of the psychiatric hospital.
In the security guard's duty room, Xu Mo found a book: *Dream of the Red Chamber*.
What stood out was that the corners of the book were slightly curled, a sign that it had been read multiple times.
Finding such a well-worn book anywhere in the hospital wouldn't have surprised Xu Mo, but the fact that it was in the security guard's duty room, on Old Ding's bedside, was puzzling.
Old Ding was practically illiterate—he could barely write his own name. How could someone like him have a book, and one that had been read so many times, by his bedside?
"Old Ding, is this book yours?" Xu Mo picked up the well-worn copy of *Dream of the Red Chamber* and asked.
"Yes, it's mine," Old Ding nodded. "I have sleepwalking issues. I picked up this book during one of my sleepwalking episodes, and ever since, I've been sitting by the bed and flipping through it whenever I sleepwalk."
Sleepwalking? Xu Mo was momentarily stunned.
It was at this moment that Xu Mo noticed the calluses on the left side of Old Ding's right middle finger and the pad of his thumb.
These were marks left by years of holding a pen. Many people have calluses in these areas, but someone like Old Ding, who could barely write his own name, shouldn't have such calluses.
Yet, Old Ding did have them, which meant he could read and write... and the well-worn book by his bedside confirmed this.
Xu Mo recalled Old Ding's behavior earlier when everyone in the hospital was asked to write a passage. Old Ding had "drawn" his name, taking a long time to "draw" out the words. At the time, his performance seemed natural, with no signs of deliberately hiding his abilities. Based on that, he shouldn't know how to read or write.
But now, it seemed he both could and couldn't read? There was a contradiction here... Xu Mo narrowed his eyes as he studied Old Ding.
"Officer Xu, what's wrong?" Old Ding asked, confused by Xu Mo's strange expression.
But Xu Mo didn't respond, lost in his thoughts.
After a while, Xu Mo snapped out of it and looked at Old Ding again.
"How did you find out about your sleepwalking?"
"I didn't know at first," Old Ding explained. "My colleagues told me. Sometimes when they leave late, they see me reading in the duty room at night, or even scribbling with a pen. But I have no memory of it. Isn't that sleepwalking?"
"I see..." Xu Mo murmured, nodding.
At the same time, he glanced around Old Ding's duty room and noticed an old-fashioned aluminum flashlight on the small table by the bed.
This type of flashlight was solidly built, feeling like a hollow metal rod when held.
Xu Mo instinctively picked up the flashlight and examined it. There was a small dent on the end, as if it had been dropped.