(Characters and incidents used in this drama are fictitious.)
(Wuseong-dong)
Wuseong Serial Murder case. A total of 10 victims.
The murderer of Wuseong Serial Murder...
who's gone off the grid for 30 years after May of 1988 is...
now on the move again.
She got out of the car and went off on her own.
He called to see if she's okay, but she won't pick up.
(Episode 29)
Name, Lee Kyung Ja.
She was the 11th target and the sole survivor...
of Wuseong Serial Murder in 1988.
She was murdered with the same MO.
Instead of going home, she came to her friend's house, but...
Step aside.
Her teardrops have dried up.
(National Forensic Service)
- Aren't you going to wear a mask? - I need to smell this.
If you're going to assist me, stay. If you aren't, leave.
This is my autopsy room.
Go ahead. I'll assist you.
Current time is 9:37am.
I will begin the autopsy.
Depressed fracture on the back of the head.
"Depressed fracture on the back of the head".
(Depressed fracture: A broken bone with a depression)
Take close-up pictures.
Teeth marks...
on the right side of the neck.
"Teeth marks on the right side of the neck".
(Teeth marks: Bite marks)
Right shoulder blade, a stab wound.
"Right shoulder blade, a stab wound".
(Stab wound: Wound from a stab)
Probe.
Right here.
Depth, 15cm.
"Depth, 15cm".
Length, 4.2cm.
"Length, 4.2cm".
Width, 0.5cm.
"Width, 0.5cm".
I see ligature mark on the wrist.
"Ligature mark on the wrist".
The fingerprints are all intact.
Since everyone knows who she is, there was no need to damage those.
Scalpel.
Right here.
Wait, one second.
I need to check something before you open her up.
One second.
What is he doing?
What are you doing, Doctor Baek?
I can smell oil.
Did she ever smell like oil while she was alive?
No.
I don't remember smelling oil on her.
Request a chemical analysis.
- It's an emergency. - Okay.
You can go ahead.
The MO is exactly the same...
as Seong Hye Bin's case except for the depressed fracture.
About the depressed fracture, where was she hit?
She was hit exactly on the cerebellum.
The cerebellum is in charge of human movements.
She probably couldn't move any longer.
Why do you think he suddenly changed his MO?
To kill with ease...
after immobilizing his victims.
He was a young man in his 20s 30 years ago.
But he's now a middle-aged man in his 50s.
We can't conclude that he's in his 50s.
His profile from the past case may have been erroneous.
Why do we do an autopsy if we can't come to any conclusions?
What did you do?
What did you do with the victim's body before you?
I smelled it. I looked for any weird smells.
All the smells were gone after Seong Hye Bin was buried,
but this time, it remained.
Are you saying you'll catch the murderer with the smell?
Wait.
What can you figure out with smell?
Anything is fine. Tell me.
I don't know yet.
We need to find out what that smell is.
What kind of nonsense is this?
Why do you even bother to say something so vague?
He started leaving depressed fractures.
This is an evolvement of his MO.
He's looking for easier ways to kill.
They're here.
Prosecutor Do, do you admit your investigation was unreasonable?
Couldn't you have stopped this if you requested...
protective custody?
Please say something.
- Say something. - Prosecutor Do!
Tell us.
A survivor of Wuseong Serial Murder from 30 years ago...
was found dead due to the prosecution...
and the police's unreasonable investigation...
which has shocked many.
The victim, Lee, even changed her name...
and lived in hiding to run from the murderer.
However, it is believed...
that the victim was found once again by the murderer...
after this investigation reopened.
Lee went out of contact on her way back after she gave her testimony...
per the investigation headquarters' request.
Then she was found dead the next day...
at her friend's house.
The investigation headquarters believe that...
the culprit felt threatened after the investigation reopened...
I told you to take in the serial murderer,
and you go and let our only survivor die.
I heard you're the one who brought her out.
Give me just a little more time.
We specified the core victims, and we're keeping a 24-hour watch.
What if...
we see another victim?
If this becomes another cold case, we'll all have to resign.
Understand?
What about Kang Chi Soo?
Yes.
He's at his studio working as if nothing has happened.
We can't see any more victims. Let's arrest him without a warrant.
Invalidate his passport.
We're going to arrest him immediately without a warrant.
- Lieutenant Cha, please get moving. - Okay. Let's go.
We need to invalidate someone's passport.
- What about the victim? - Yes, thank you.
Prosecutor Eun.
About the possibility of a copycat,
I asked a junior of mine who's in the cyber investigation team...
to go through the internet.
And they found this.
This website is like a genealogy of the murderer...
of Wuseong Serial Murder.
Who runs this website?
You know what's funny?
We know him.
What?
The substance found on Lee Kyung Ja's stab wound is...
rifle bore-cleaner.
Rifle bore-cleaner? Isn't that industrial grease?
And it's made in accordance to the military specification.
This rifle bore-cleaner is...
used to clean out leftover gunpowder from the muzzle.
The bullet can't leave the gun with extra gunpowder piled up.
It's a must in the army.
You reek of oil after you clean up your gun.
Something is very strange about this situation.
Our perpetrator must be a strange soldier.
And the smell was pretty strong.
Good point.
The ones used nowadays don't smell as strong.
This isn't made according to the current military specification.
I did some research...
and found out that it was used in the 60s and 70s.
It was mainly used for the Vietnam War.
The Vietnam War.
Does anyone use this nowadays?
We can go and find out.
Where to?
Goodness, this place has everything.
You aren't here to shop. Hurry up.
There's a lot of stuff here. I'm sure we'll find it here.
- Hello. - Hello.
We have a question.
Do you have the M-series made by Octagon?
Octagon? We don't carry such an old product.
They have a few things here.
Here?
Let's go... Okay.
- Hello. - Hello.
Excuse me, sir.
I'm looking for the M-series made by Octagon.
- Do you have any? - I'm not sure.
Right, one second.
Stay seated.
It's been forever, Joon Tae.
I heard the rumor too.
It was interesting.
(Kim Joon Tae, 22, Yeon Mi Rae's boyfriend, in prison)
The culprit of Wuseong Serial Murder was...
your idol, wasn't he?
He's the textbook model of an evolving murderer.
He killed all 10 of his victims in different ways.
Isn't that amazing?
I heard you know the best...
about the culprit of Wuseong Serial Murder.
I followed his formula...
when I framed Cha Soo Ho for my murder.
Darn it, this jerk.
- What's the formula? - "Never kill on an impulse."
"Keep your eyes on your target,"
"find out their pattern, and look for the best time to kill."
"Don't leave evidence..."
"or leave misleading evidence that will derail the investigation."
Aren't you stuck?
How dare you? Where are your manners?
There are things that I didn't put on the blog.
You look curious.
Shall I tell you?
- Or not? - This little...
Joon Tae.
Let's go with tell.
Investigators trust each other too much, and that's a problem.
180cm tall, shoe size 260mm.
- What kind of lie is that? - Hey, come on.
Some men have small feet.
Did he have small feet or...
was he short?
The Wuseong killer's victims...
were all short below 160cm in height.
If he were 180cm tall,
he could've killed taller women.
Sir, do people still ask for this?
Old people do sometimes. Old habits die hard.
Hello. Right now? Okay.
They're arresting the Wuseong killer.
They want us on the scene.
Secure a path for retreat and call in when ready.
If we block here and here,
we should have him.
Baek Beom speaking.
- Where are you? - Why?
The killer could be shorter.
We can't trust the old profile.
- He could be over 50. - What?
They're going to arrest Kang Chi Soo.
Yes, I'm here.
It's not Kang Chi Soo.
The profile that he's in his 50s is wrong.
- Give me that thing. - Here you go.
What are you doing?
The murder weapon, a military M7 bayonet.
Rifle bore-cleaner used to wipe it.
- You found it? - The smell from the corpse...
was from this rifle bore-cleaner.
It really stank because it was made to 1960s' army specifications.
What does that smell have to do with the killer?
That's the wrong question.
Rifle bore-cleaner's for the muzzle. Why was it on the stab wound?
Keep going.
The killer's not in his 50s. He's older.
I say 70s or older.
These were used by the army in the 60s.
They were low on supplies then...
and wiped their bayonets with muzzle cleaner.
The killer still maintains his weapon that way.
The facts on the body don't lie.
We're ready. What should we do?
Bring him in.
- Let's go. - Yes, sir.
Sorry, but your claim...
is quite interesting.
Let's go.
We're going in.
Mr. Kang Chi Soo?
Why run away? We're here to talk.
Take him.
- You got him? - Yes.
That's the darkroom.
- Hold him down. - Okay.
A remodeled bathroom?
We'll check for blood.
Okay.
Lights off.
It's all blood spatters.
It's over. We have him.
Arrest Kang Chi Soo and get the NFS to investigate the room.
Yes, sir.
It's done. Arrest him.
Kang Chi Soo, you're under arrest for the murders of...
Lee Kyung Ja and Seong Hye Bin. Let's go.
Thanks for your hard work. Check the scene carefully.
- Prepare for a briefing. - Yes, sir.
That'll do.
Swab the bathtub, walls, and floor.
Isn't this familiar?
It's what you did often...
30 years ago.
What did you do on the 10th and 17th of July?
I was out to take photos.
Why did you try to run away earlier?
30 years ago,
you people harassed me the same way.
When I think about that time,
I still shudder.
Why did you come back to Wuseong, the place that makes you shudder?
Did you miss the old days?
There's no place like Wuseong to kill, is there?
You know all the shortcuts,
and there are no cameras in the rundown neighborhoods.
Do you have evidence?
- What? - Bluffing without any proof.
Just like 30 years ago.
When the blood spatter results come out,
you won't be able to say that, okay?
You illegally remodeled a bathroom into a darkroom.
- Let him go. It's not him. - So you could kill again.
- What? - Old habits die hard.
What are you talking about?
Give me that.
Let's compare.
Isn't that strange?
You returned from Canada...
- What are you doing? - And more died after 30 years.
Right in Wuseong-dong.
Do you see this?
It's iron dust.
The lens caps of old film cameras are made of iron.
So what if they are?
Luminol reacts with hemoglobin,
in other words, the iron in blood.
It reacted to actual iron dust as well.
The sparkle you saw in the darkroom were iron specks, not blood.
On everything we brought back,
we found iron dust or specks and black paint coated on the camera.
There was no blood.
Hand that over.
(Component Analysis)
(Iron, Paint)
He put the lens cap on and off in the darkroom.
Dozens of times a day.
There was no blood in that room?
Not a single drop. That's not the crime scene.
- This is so uncomfortable. - Seriously.
The mold from Kang Chi Soo's teeth and marks on Seong Hye Bin's neck...
aren't a match either.
Then where did he go after closing his studio?
He was out working.
We checked his camera for photos from those days.
He took candid photos of the public for sale.
- What? - That's why he tried to run.
We proved those charges.
You helped us a lot.
I'm really sorry.
We were sure it was him.
I thought we'd get him this time.
You all can go home.
If we need your help,
we will give you a call.
- Thank you. - Thank you.
- Gosh. - Darn it.
"A Doberman never lets go once it bites."
- I thought you were a Doberman. - Yes, and your point is?
Why are you beating yourself up for it?
No, I'm not.
I'm waiting for my noodles. My blood sugar is low.
Do you want some?
I'm fine.
Goodness.
I really thought that we had him.
I don't know where we went wrong.
This is driving me crazy.
Is this how you solved cases at the Central District?
Usually, you seem to be cautious, but once you're fixed on an idea,
you try to see it through even if others try to stop you.
And in the process, you got demoted. The news is all over the place.
Really?
When owners can't take care of these rabid dogs,
they send them away out of their house.
Why are you eating by yourself?
What? What is it? Are you going to say...
that pain halves when shared or something like that?
My gosh, forget it.
Reflecting on one's mistakes ought to be done alone.
Come on, did you investigate by yourself?
If we apprehended the culprit,
were you going to take the credit all for yourself?
My gosh, you're terrible.
Did I sound like that?
I'm heading somewhere. Do you want to join me?
Where?
(Under Investigation, Off Limits)
There wasn't a single drop of blood.
He washed it with water.
My gosh.
Dr. Baek.
"The culprit always returns to the scene of the crime."
You completely fit that profile.
What are you doing in the tub?
- He washed it. - What?
The culprit washed the body.
When the artery is cut, at least 3L of blood will gush out.
That's why he killed her in this tub.
30 years ago,
it was doable to kill women on desolate hills or rice paddies.
The blood would have been absorbed into the soil.
But that won't be easy these days.
There are a lot of people and cars. They are all possible witnesses.
That's why he killed her inside the bathroom.
The blood will be washed out.
However, he would have left a definite trace.
I have something to announce to you all.
We're going to completely reexamine the culprit's profile.
- Pardon? - Sorry?
He may be shorter than 180cm and over 50.
We will broaden his age to men in their 70s.
What are you talking about?
Are you going to believe in Dr. Baek's opinion?
(Wanted)
From this point on,
we'll start our investigation at square one again.
I cannot allow this.
Are you going to throw away all of our hard work until now?
I'm sorry, sir. Even if you disagree,
the direction of the investigation has already changed.
Fine. Then do whatever you want.
- I can't allow this. - Wait, sir.
Let's continue.
All right. We have a lot to do.
The culprit always drains out...
the victims before he disposes the bodies.
In the process, the usage of water must have increased.
The average amount of water a person uses in 1 day is 500L.
From the body, about 3L of blood comes out.
To completely remove all that blood, he would've needed 10 times of that.
Then he must have used at least 5,000L.
That's right.
I'll put together a list of households...
whose water usage skyrocketed all over Wuseong-dong.
The substance that was found in Lee Kyung Ja's stab wound.
It's a rifle bore-cleaner, produced in the 60s for military use.
You can only buy this from military collector shops or websites.
Including the websites, look into every seller.
And give me a list...
of people who bought this product over the past six months.
Yes, sir.
Prosecutor Eun.
I came to the management office to measure the water usage.
In order to search every household in Wuseong-dong,
they have to manually program the households.
They said that it will take about 1 or 2 days.
That long?
Or we have to check the meters one by one...
and check the accumulated usage until today.
We can only use that method after narrowing down the sample.
Okay.
Gosh.
We have the list of people who purchased rifle bore-cleaners.
We can't identify them since they used their usernames.
We only picked out people who got their package in Wuseong-dong...
during the past six months.
- How many do we have? - 38 people, sir.
We might be able to...
find him by today if we dispatch more people on that.
- Sir, I'll see you on the field. - Okay, drive safely.
(Seoul Eastern District Prosecutor's Office)
Yes, we're from Seoul Eastern District Prosecutor's Office.
- May I check your water meter? - Okay.
Here it is.
Unit 104.
- It's 480. - 480?
That's too little. This isn't the house. Let's go.
Deputy Yang, why don't you go that way? I'll go this way.
Yes, sir.
Excuse me.
Is anyone home?
Excuse me.