Chapter 288: Castor Toxin

The little boy that Xu Mo brought back is very young, and he doesn't seem very brave.

You can tell at a glance that this kind of person has just entered society not long ago.

Han Fei, a veteran with decades of experience, finds it quite easy to deal with someone who has only just entered society.

In fact, just by looking, he can see that the kid has little suspicion.

But to ensure there is no mistake.

Han Fei still decides to ask a few more questions, lest his judgment be wrong.

"Where were you last night?"

"Last night... I was at school. I was at school all day yesterday," the boy replied.

"School? University? Which school? What major are you in?"

"Yes, university. I'm at Yangcheng University, majoring in Financial Management."

"Can anyone vouch for the fact that you were at school all day yesterday?"

"My teachers and classmates have seen me; they can confirm it. I also slept in my dorm at night, and my roommate can testify."

He answered without any hesitation, seeming unafraid of investigation, and Han Fei began to have doubts in his mind.

The kid already had little suspicion, and now he says he was at school all day yesterday, completely clearing the little doubt about him.

Being at school all day means he had no time to commit the crime at all.

"You...," Han Fei began to ask, but he was cut off as soon as he opened his mouth.

It was the forensic doctor who interrupted Han Fei.

"Han Team, the autopsy report is ready; take a look,"

Saying that, the forensic doctor handed the printed autopsy report to Han Fei.

He didn't state the cause of death directly in front of Han Fei because there was an outsider at the scene, making it inconvenient to speak.

Han Fei also realized this.

After receiving the autopsy report, he immediately stood up and moved away from the little boy sitting at Xu Mo's workstation.

The forensic doctor and Xu Mo followed right behind.

After walking a short distance away,

the forensic doctor spoke.

"Xu Mo is correct; the victim indeed died of poisoning. Tests show the toxin that caused death is Castor toxin, which comes from Castor seed. Castor toxin is highly toxic, has no antidote, and poisoning is virtually certain death."

"Castor toxin?" hearing the forensic doctor's words, Xu Mo pondered, "If death was caused by this toxin, the victim couldn't have committed suicide; it must be homicide!"

"Why?" Han Fei asked.

"Yes, yes, it's homicide; I was just about to state that," the forensic doctor said, looking at Xu Mo with surprise.

He had just been about to tell Han Fei this, but Xu Mo beat him to it.

It seems Xu Mo not only can handle basic autopsies but also has knowledge of toxicology!

The next second, the forensic doctor spoke and explained to Han Fei.

"Han Team, you might not know, but in toxicology Castor toxin is also called Perfect poison; it's definitely the assassin's poison of choice. People who die from it are usually assassinated. If it's not homicide, it would be accidental ingestion of Castor seed, but I didn't find any Castor seed in the victim's stomach,"

"Perfect poison? Why say that?"

The forensic doctor couldn't think of how to answer Han Fei right away.

Seeing this, Xu Mo immediately spoke up.

"It's highly toxic and hard for medical tests to detect; symptoms often mimic flu, so victims aren't usually suspected of poisoning. That's why it's the assassin's perfect poison. People rarely choose it for suicide because it's difficult to handle; even if they did, they'd have to ingest massive amounts of Castor seed, yet no Castor seed was found in the victim's stomach—he died from Castor toxin,"

The forensic doctor nodded.

"Exactly, that's it. The main point is it's hard to detect, so people rarely suspect poisoning,"

Han Fei frowned.

When all investigative avenues proved dead ends, Han Fei wondered whether they might have misjudged.

The victim might have committed suicide instead of being murdered.

But now that idea has been overturned.

Even though he doesn't understand toxicology.

Nevertheless, Xu Mo and the forensic doctor have already explained Castor toxin to him in the simplest terms.

In their words, it's the assassin's perfect poison; if not homicide, what else could it be?

The killer chose this toxin precisely because it's hard to detect medically; he wants to pull off the perfect cover-up!

He wants the Police to think the death was accidental.

Having learned this, Han Fei felt even more of a headache.

What aches is that they can now confirm it's a murder case.

But he hasn't found a direction for the investigation; he's in a fog.

"Could it be a Crime of passion?" Han Fei muttered.

That thought made his headache worse.

Among homicide cases, the hardest to solve are Crimes of passion.

Because the killer acts without any pattern.

They might even kill on a whim, killing whomever they feel like, with no logic at all.

Conventional investigative methods simply can't uncover any clues.

After all, before the killer murders, they may have had no relationship with the victim; at most they met once at the time of killing.

Where can one investigate that?

Checking the victim's social connections? That won't help either!

At that moment, Xu Mo, as if he had suddenly thought of something, spoke up.

"Han Team, I have an idea."

"What?"

"I think the possibility of a Crime of passion can be ruled out outright," Xu Mo began to explain. "The characteristic of Castor toxin is that it is not easily detectable by medical means, indicating that the murderer wants to mislead the Police, making them think the death was accidental. If it were a Crime of passion, the murderer wouldn't need to bother misleading the Police at all."

Since he chose Castor toxin to kill, doesn't that imply that the murderer actually had a link to the victim, and he didn't dare use an overly obvious method because he feared the Police would follow the clues and easily locate him? In other words, who the murderer is is actually quite clear; it's just that our investigative direction is a bit off, which prevented us from suspecting him right away.

Upon hearing that, Han Fei's eyes clearly lit up.

"You mean Dark under the lamp?"

"Exactly!"