Original subtitles

(Mouse)

(This drama is purely fictional and is not associated with...)

(actual people, organizations, locations, or incidents.)

(Filming was in compliance with COVID-19 guidelines...)

(and counseling was provided for child actors.)

(CGI was used in most scenes that include animals.)

(Mugwan Boxing Club)

We're closed.

So you used to box.

No wonder.

Excuse me.

Who exactly are you?

Why did you kill them?

My family.

Did that finally ring a bell?

It's unfair though...

since I never once forgot about your existence.

I've been searching for you all my life.

I became a cop to track you down more easily.

Your face and fist.

That's all I had to go on...

which made the search tricky for me.

Get up here and show me what you've got.

(Bible)

Eye for eye.

Tooth for tooth.

That was for beating my mom to death.

This is for my younger brother who burned to death.

And this is for what you did to my stepfather.

(Mouse)

(Episode 17)

What do you plan to do now? Tell me what you plan to do!

I can't live with him anymore.

He...

He buried his own little brother.

I knew he was nuts when he killed our goldfish and Choco.

He'll end up killing someone one day.

That's enough. He can hear you.

Darn it.

Look at those darn eyes.

- Quit glaring at me. - Honey.

My gosh.

Jae Hoon, come over here.

You need to wash.

You must be hungry.

Where's Jae Min and Jae Hee?

Your dad took them to an amusement park.

Don't get me wrong.

I wasn't trying to kill Jae Min.

He kept tattling on me,

so I just wanted to teach him a lesson.

That's all I wanted to do.

I mean it, Mom.

Okay.

Go ahead and eat.

Mom. What are you doing here?

You monster. Die.

Die!

Jae Hoon.

Die! Die!

Mom.

Mom.

Mom.

Jae Hoon.

I'm sorry.

I'm sorry I didn't believe you.

Mom.

I didn't...

have a choice.

You were born...

with a special kind of gene.

Why...

Why only me?

No.

There's more.

There's one more kid...

who was born just like you.

My poor baby.

Mom. Hang in there.

Mom.

My son.

You're a kind son, right?

I hope...

you live..

a kind and upright life,

my baby.

- Oh, dear. - My goodness.

Oh, my goodness.

Poor kid.

What in the world happened?

- What's he going to do? - Exactly.

("Entire Family Murdered in Guryeong")

He's not even crying even though his family's dead.

You shouldn't do that to a kid.

Did you witness anything that day?

No, I didn't see anything.

How dare he kill my family.

I'll chase him down and do to him exactly what he did...

to my family.

It's revenge murder.

I'm taking revenge.

Let me borrow this photo.

Why? What for?

I need to look into something.

I'll tell you next time.

Did Soo Ho continue to box?

No. He quit boxing...

not too long after what happened to his sister.

Around that time, he worked for a company.

A company? Where?

It was some security company.

He was having such a hard time,

that he received counseling...

at a government-sponsored center.

They recommended him for the job...

at the company.

He worked there for about 10 years.

He worked hard and diligently.

Then one night,

he bawled all through the night.

Soo Ho. What's wrong?

- It was the first time... - What is it?

he cried out loud ever since his sister died.

The next day, when I was cleaning his room,

I found a receipt for the Guryeong tollgate.

He quit right after that...

and helped his friend at his boxing gym.

Guryeong.

He never said what happened?

I asked once, but he wouldn't say.

Also, a few days after that night,

a detective came by.

He asked him a few questions,

and just left.

A detective.

This is Guryeong Lake, right?

He never told me...

why he killed my family.

Burglary?

No. He would've killed me too then.

Why did he remove me from the house and then set it on fire?

Why only me?

This man...

He looks very familiar.

You should've let me die!

Why...

Just why?

No wonder. I knew he looked familiar.

You should've just let me die.

Then he never would've been born.

- Why did he save just me? - Why did he save just me?

Sung Yo Han went to grade school in Guryeong.

So this kid is Sung Yo Han?

Okay. That connects him to Song Soo Ho.

May I help you?

Police. I'm looking into a few things.

What could the police want with this house?

Right? National Son Officer Jung.

Goodness.

I saw you on the news.

You've suffered so much because of that scumbag.

You're here because of Sung Yo Han.

Sung Yo Han?

I almost fainted that day when I saw the news...

because I thought he was Jae Hoon.

What...

That day, Sung Yo Han came...

and stared at this house for a really long time.

Sung Yo Han was here?

- That day, as in... - You know.

The day he was shot.

He came during the day and stared intently at it.

I looked to see who he was,

and he was about Jae Hoon's age.

So I went,

"Is it you, Jae Hoon?"

And he said no, and that I was mistaken.

Then he scurried off.

He did?

Yes.

That's right. He stopped and asked me...

about the twin girl who lived here.

About Jae Hee?

Their youngest daughter went missing, you see.

They only found three bodies.

Everyone said...

their eldest son probably killed them.

That he probably killed his sister and buried her body somewhere.

Jae Hoon was very strange, you see.

I wonder where he is and what he's doing.

I wonder if he's even living like a decent human being.

I hope he grew up to be a good person...

like you, our National Son.

Thank you.

Why did he come here?

How did he know Jae Hee?

She went missing in 2005.

She would be 22 years old now.

Her name when she went missing was Jung Jae Hee.

Also, she had Savant Syndrome.

She remembered anything she heard once.

There was no child...

with a condition like that reported missing in 2005.

I'll check with the Disabled Human Rights Center.

Thank you.

Please find my little sister.

This is Jae Hoon from class three.

- Not Yo Han. - Jae Hoon?

Yes. Jung Jae Hoon.

Haven't you heard of the Guryeong Family Massacre?

He was their eldest son.

The Guryeong Family Massacre.

I found a receipt for the Guryeong tollgate.

He bawled all through the night.

A few days after that night,

a detective came by.

What happened to this child after that incident?

I think I heard that his relative took him.

Try the police station. It would be faster.

Thank you.

The house is still in the parents' name.

That's why it hasn't been torn down, and remains as an eyesore.

What about the twin girl who went missing?

- The daughter? - Yes.

We never found her.

Hello.

Hey, Ba Reum.

- Detective Ko. - Why won't you answer your phone?

I needed to look into something. What are you doing here?

I'm Detective Ko Moo Chi from Moojin.

Is the detective who investigated

the Guryeong Family Massacre still around?

That was my case.

Good.

Do you remember this boy?

That's their eldest son.

That was the day I drowned Choco.

Was he a suspect back then?

He made the list briefly, so I went all the way to Moojin.

What happened?

Just a minute. I need to check my file.

He wasn't there.

I checked out all the suspects from the case when I became a cop,

and he wasn't there.

It's not there.

That's odd. Why is he missing?

I prepared an investigation report.

It went missing?

That's odd. Who could've made such a mistake?

The eldest son is there. Here's the investigation report.

The eldest son? Him?

He was a suspect too?

But he was their son.

Well, even after what happened to his family,

he didn't show any sadness. He was apathetic.

He was so suspicious,

that we even secretly did a polygraph on a kid.

- And? - It was negative.

An 11-year-old wouldn't kill his own family.

We only did it because it was so frustrating.

Do you know where he is now?

His maternal aunt took him.

His aunt? Can I get her contact information?

Here it is.

(Guardian: Aunt)

The number you have dialed is not in service.

It's not in service.

Can we look up the aunt?

Just a minute.

(National ID Number)

Why won't anything show up?

That's odd.

I remember checking her ID.

Can you look up this boy instead?

Sure. Just a second.

It'll show that I'm Jung Jae Hoon.

What do I do?

His registration number expired.

- Expired? - Expired?

That means he either died or went abroad.

That's not the same as mine.

Auntie said she adopted me,

but she had my number expired instead.

So whose registration number am I living with?

So what brought you here?

While investigating Chi Kook's murder,

I looked into his case file...

to see if Sung Yo Han had any accomplices.

He once lived in Guryeong,

so I thought I could find something here.

By the way, where did you get the photo of that kid?

From Song Soo Ho's album.

He also had OZ tattooed on his arm,

so I went to his mother to confirm.

I'm guessing he was involved in the murder of this boy's family.

Song Soo Ho's in on it too?

According to Song Soo Ho's mother,

he wept all night when he got back from Guryeong...

and it was around the time the boy's family was murdered.

The organization known as OZ which he was a part of...

must be in league with the psychopath...

that killed Kang Duk Soo, Lee Jae Shik, and Kim Byung Tae.

He's been dormant lately, but he will resurface soon.

Psychopaths like him can't go long without killing again.

We should head back before it gets dark.

You were born with a special kind of gene.

There's one more kid...

who was born just like you.

How could Mom have known that?

A unique gene?

Did you know from the get-go...

that I was a predator?

Would I have asked you to work with me had I known?

- I was certain it was Sung Yo Han. - How were you so sure?

Because I ran a psychopath DNA test on Han Seo Joon's fetus.

From where did that car start following me?

Okay.

If Song Soo Ho killed the boy's family,

the boy would've wanted revenge.

But this boy isn't Sung Yo Han.

However, Sung Yo Han killed Song Soo Ho out of revenge.

What's going on?

Sung Yo Han tried to kill Na Chi Kook,

but someone threatened him after he woke up...

and he was finished off by Mr. OZ.

This is nuts.

Wait.

Isn't this evidence...

- related to Sung Yo Han's case? - Yes.

Why are you looking into them?

I can't do nothing while Moo Chi doubts Sung Yo Han as the killer.

So I thought I'd go through them all...

to present definite proof.

Go on.

Hey. Where are we...

with the fingerprint on the written statement?

The lab checked the database...

and it showed a set belonging to a third party.

But it's not clear enough for a positive ID.

Where's Detective Lee right now?

Am I doing the right thing,

Jennifer?

What brings you by unannounced?

You tricked me.

Darn those annoying jerks.

- What's wrong? - The cyber unit...

is accusing us of damaging the security footage...

that we watched the other day.

What do you mean it was damaged?

Apparently, Moo Chi took the video with him...

to check if it was edited.

What are you talking about?

That I was born with a special kind of gene...

and that another boy also was born with it.

How did my mom know that?

That's you?

You're Min Kyu's son?

The son of Park Min Kyu and Kim Hee Jung?

That's right. Those are the names...

of my birth parents.

I was certain that your mother...

would choose to have an abortion.

An abortion?

Is this what you're looking for?

Where's Detective Lee right now?

Off for a smoke, I guess.

- Nepo. - Yes?

When he gets back,

let him know indirectly that I know about...

the edited CCTV footage of the lobby.

- Sorry? - I must see for myself...

how he responds.

Is this what you're after?

Are you worried I finally have you on video?

What are you ranting about?

Then why were you going through my desk?

Come with me.

What on earth are you doing?

Hand. Let me see your hand.

Darn it.

Here it is.

I see you were in a hurry.

You got nervous.

What are you people? An organization of psychopaths?

Reveal yourself!

What are you getting at?

I had my ex-girlfriend's initials burned off after the breakup.

Really? Then explain the edited CCTV footage.

You let Mr. OZ look at Kang Duk Soo's statement.

What are you accusing me of doing exactly?

The CCTV footage has been restored, so see for yourself!

Is it perhaps this?

I dropped the statement in the lobby...

and someone picked it up for me.

Also, I never edited any CCTV footage.

I get it.

We don't get paid enough on this job.

We barely make do.

Do those guys pay you enough?

Darn. What are you talking about?

You're a stinking rat.

Money?

It's a sense of duty that drives me.

Hey.

Hey, where did you get this jacket?

- It looks nice. - Darn.

- Get lost. - Let me see which brand it's of.

Gosh, that's hot.

I'm sorry about that.

You should take it off.

- Sorry about that. - Are you okay?

Detective Shin, must you be so clumsy?

Goodness. Are you hurt?

Detective Lee, your skin is burned.

I said I'm fine.

- Right. - This must be water-resistant.

It's too bad it smells like coffee now though.

How about you sell it to me for a cheap price?

- Forget it. - I'm sorry, okay?

Did you get a look?

- Moo Chi! - Yes?

You were right about it being a burner phone.

The call came from the Ministry of Science and ICT.

- The Ministry of Science and ICT? - Yes.

Shouldn't we open an investigation on Detective Lee?

For what? Burning off his tattoo?

That he uses a burner phone?

He edited the CCTV footage.

There's no proof that he actually tampered with it.

The video alone...

doesn't prove that he's working with Mr. OZ.

Going after him with only a hunch can make it worse for us.

Why did you accuse him then? It only put you in danger.

I at least know for sure now,

so let's keep a close eye on him.

Check whom he meets...

- and whom he talks to. - Got it.

Are you still searching for the unregistered 6264 sedan?

I am,

but it'll be nearly impossible to track...

unless it gets in an accident.

By the way, where on earth is Officer Jung?

It'll be just the three of us for the time being.

Why?

Something just doesn't feel right.

Your father was a member on my research team.

To help with the research, he persuaded your mother...

and had their baby's genes tested.

The baby turned out to have the psychopath gene.

I had no other choice but to speak the truth.

I advised them to get an abortion and they agreed, so...

I had no idea that they brought the child to term.

You said that psychopaths are selfish beings.

But the fact that I got revenge on Song Soo Ho...

proves the love I had for my family.

It wasn't out of love.

"How dare you mess with what's mine?"

"How dare you invade my territory?"

That's how it triggered you.

(Song Soo Ho, OZ 1)

I had to kill an innocent man because of you!

I ran it in the database of ex-cons and found him.

(Shoulder, finger, pubis)

- I'm your aunt. - Mom had no sister.

His registration number expired.

(Song Soo Ho, OZ 1, Uncle, Aunt)

The guy who witnessed my murder and ran away.

I was determined to find him and get rid of him.

Officer Jung!

- Detective Ko. - But I ran into Detective Ko...

and failed to find the witness.

But as soon as I saw Detective Ko's jacket,

I was reminded of the jacket I saw.

(Shinara Dry Cleaning, Nam-gu, Moojin City)

(Shinara Dry Cleaning)

Yes, that's right. I took Kim Joon Sung's laptop.

I took photos of the victims while they were still alive.

But these were taken after they died.

They're just like the photos that were at Sung Yo Han's place.

So he watched me kill the victims...

and took photos of them after they died...

without even calling the cops?

He was also one of them.

(OZ 1, Uncle, Aunt, Sung Yo Han)

No.

Sung Yo Han tried to kill me.

Why did he try to kill me unlike the other OZ members?

Song Soo Ho killed my mom in order to save me.

But why did Sung Yo Han try to kill me?

Save the boy first.

Han Kook, who's below your feet.

He was trying to save Han Kook.

If he was an OZ member,

he would've taken care of Han Kook's body to cover for me.

We...

are...

What did he say?

What did he say?

We...

are...

I need to check.

(Song Soo Ho, OZ 1, Uncle, Aunt, Sung Yo Han)

He called someone here, but whom could it be?

Could it have anything to do with the fact that Kim Joon Sung...

worked for the Ministry of Science and Technology?

Does that mean Kim Joon Sung was also an OZ member?

I didn't see anything.

Are you sure?

Officer Jung, my job is to examine dead bodies.

I'm sure I remember it correctly.

There was nothing.

By any chance, did you carry out an autopsy on Sung Yo Han?

No, his mother didn't want it.

Does that mean Kim Joon Sung wasn't one of them?

Then what about Sung Yo Han?

- Officer Jung? - Yes.

He asked the same question as you.

He asked if Kim Joon Sung had an alphabet tattoo.

What is he trying to find out?

I didn't have time to check for that.

He was shot in the abdomen, so that was all I was focused on.

Is there anyone who was close enough to know if Sung Yo Han...

had anything on his body?

No, not really. He had a cold personality,

and he never opened up to anyone.

Where do I need to go to check this?

No, we don't have any videos of the surgery.

You don't?

It was the first brain implantation in the entire history of mankind.

I'm sure you shot a video to leave a record.

Han Seo Joon wanted us to keep it confidential.

Not only did he say no to the shoot,

but he also didn't want anyone else in the OR other than himself.

He didn't want anyone to know how it was done.

I still don't get why since he's a death-row convict.

That kind of medical technique should be shared with everyone.

So it's a real pity.

Plus, even if we did shoot a video,

we wouldn't have shot

any other parts of the body considering it was a brain surgery.

Okay.

Wait.

Do you not have severe headaches anymore?

I'll prescribe you some medicine. Go pick some up from the pharmacy.

He's a real nutjob.

I can't believe he made this work.

What a waste.

If he wasn't a murderer, he would've become a world-famous...

But then again,

maybe he was able to succeed because he killed all those people.

How ironic.

Don't try so hard to die.

You don't have much time left anyway. You'll die too.

Ba Reum.

I'm tired.

Why are you being like this?

You're very dull. Why do you think so?

I don't like you anymore. You make me feel uncomfortable.

Just go home.

I know it's because of Kang Duk Soo.

I already know.

I know you killed Kang Duk Soo.

That's why you keep avoiding me.

You...

Ba Reum, I don't care.

Kang Duk Soo deserved to die.

If you didn't kill him, Yu Na would've died instead.

- So... - Yes, that's right.

I killed Kang Duk Soo.

It was because of you.

I killed him because I thought you'd be dangerous.

Look what you made me do.

I should've just let him be, but you made me become a murderer!

- Ba Reum. - You remind me of that day.

It's a complete nightmare!

So please get out of my life.

Ba Reum.

If you show your face again,

I'll confess to killing Kang Duk Soo and will go to jail.

Unless you want to see me rot in jail for the rest of my life,

don't show your face to me again.

I remember everything now.

Please help me. Help me.

Please help me.

That day...

Bong Yi.

Help me.

Please help me.

If I had...

Please help me.

What should I do, Bong Yi?

What should I do?

If this child, not Sung Yo Han, was the murderer...

Chi Kook knew that, so he threatened and killed him.

Then why did Sung Yo Han try to kill Officer Jung?

What about the photos of the victims in his house?

(He had a grudge against Song Soo Ho.)

(Kang Duk Soo, Lee Jae Shik, Kim Byung Tae)

(Kang Duk Soo's mother's statement? An insider.)

(Black midsize sedan, OZ!)

(Hideout? Motel in the northern district.)

Hold on.

Did Hong Ju find out something?

Why is she suddenly doing a special on the Moojin Serial Murders?

The killer was caught already.

What?

Why are you doing another show on the Moojin Serial Murders?

You found something, didn't you?

Like what?

The one who killed Kang Duk Soo, Lee Jae Shik and Kim Byung Tae...

is leaving a similar signature as Song Soo Ho's murder.

That's why I wanted to investigate again from scratch.

So there is something.

There is.

Got it.

I made this myself.

Hang it in your car, okay?

I wanted to make sure there wouldn't be another victim...

like you ever again.

But your big brother ended up...

(Detective Ko Moo Chi)

Hello? Hello?

What... Who's prank calling at this hour?

Hello?

Get your act together. You can't lose this.

That's where it was. I was so out of it.

What? Hello?

I have something to do today,

so I'll pick it up tomorrow.

Looks like Jung Ba Reum has been using a burner phone.

Locate the origin of the signal.

Find out whom he contacts.

He's leaving for work now.

He went to work in Moojin.

I've located the origin of the signal.

Welcome to the mouse trap, you rats.

Hello?

- I can't hear you, detective. - Where are you?

Hello?

Why can't I hear him?

My phone was cloned.

I advised them to get an abortion and they agreed,

so I had no idea...

that they brought the child to term.

He knew Mom had me.

You tested my DNA,

and if OZ knew I had the psychopath gene...

and followed me ever since I was a child.

It means you were working with them.

Then I need to find out why you're living in hiding...

and pretending to be dead.

If OZ is looking for you,

I'll use you as bait.

The best way to catch a mouse...

is to set a trap with an enticing bait.

That's where it was. I was so out of it.

I have something to do today, so...

Tell me. Who are you people?

You know me, don't you?

You must know what kind of a monster I am.

If you don't tell me, I'll slit his throat and crack his skull open,

and I'll eat his brain.

One.

Two.

- Three. - Hey.

Will Oh Bong Yi be taken and found as a corpse?

Or will she be dropped off safely at her destination?

You choose.

Darn it.

He'll be safe, right?

Okay.

Where is it?

I left it there.

No.

How did it go?

I lost them.

- What's wrong? - What?

I think I left a picture.

A picture?

Of what?

My sister Jennifer.

If they find it...

I'll find it.

I'll get it.

Stay here.

He's definitely being hunted by them.

They even know his family.

What's this?

(Call log)

(Dr. Daniel Lee)

Dr. Daniel Lee?

(Voicemail)

Message number one.

Yo Han, it's Joon Sung.

This is Sung Yo Han's phone.

Daniel and Sung Yo Han kept in touch.

What you asked me to look into has me terrified.

I think I heard wrong.

The organization goes by the name OZ.

Anyway, let's talk in person.

What on earth?

Neither Sung Yo Han nor Kim Joon Sung...

were a member of OZ.

What is this doing here?

Then that day...

Here. Take a seat.

That's when I realized my diary was missing.

(October 15, 2019)

(Completely covered in blood...)

(Eye for eye, tooth for tooth.)

October 17, clear. I gutted a rabbit...

to see if it had gained weight or was pregnant.

I lost top of the class to someone else.

"This award is to honor..."

"the outstanding accomplishment one achieved on the math contest."

The transfer student who annoyed the heck out of me.

He sure was a weird one.

Others avoid me, but not him.

That's what annoys me more.

But still, I wish to be like him.

I want to be like him.

The annoying transfer student.

What good does top grades do...

when you don't know you're being followed?

That's right.

Someone was following him.

He was under surveillance.

Could it be...

It's been a year since the Moojin serial murders.

How have you been?

I've been well.

Actually, no. I tried to take my life a few times.

I couldn't breathe.

What sins did I commit in my past life...

for my children to be both...

I'm doing better now though.

I've been able to slowly move on.

And it's all thanks to him.

Him?

The grateful one who gave me back...

the will to live.

Right.

I was wrong to speak badly of the baby,

so I'll apologize for just that.

How can you keep your dog chained here...

- when you don't even live here? - I'm sorry.

I just couldn't leave it alone at home.

My Boksil is usually a sweetheart.

Unbelievable. Just take it away, darn it!

Can't you see that my baby is freaked out?

All because of your limping dog.

Did you seriously just say that?

- What? - Who knew that one could...

be this rude?

We meet again, ma'am.

I went to see you the very next day,

but you had moved.

Yes, I kind of had to.

Just tell her to leave with it!

Is she for real?

- How have you been? - You should get going.

I don't want to be in the hot seat with the homeowners association.

But the baby's mother will be home in half an hour.

Could it stay here for just 30 minutes?

It can't, so please take it away.

Why don't I take Boksil for a 30-minute walk?

Boksil, let's go for a walk.

Gosh, thank you so much. Could you do this for me?

The baby's mother will soon be here.

Sure, don't worry.

Thanks again.

Sir, could you...

give this to Unit 805 when she gets here?

- Unit 805? - Yes.

This way. Let's go.

Boksil...

- Are you all right? - I'm good.

Boksil, it's all right.

- Shouldn't you see a doctor? - No, I'm fine.

Boksil, how was your walk?

- Thank you. - Don't mention it.

Thanks to her, I got a nice walk as well.

- I'll get going then. - Just a second.

Let me make dinner for you.

No, that won't be necessary.

I live nearby and would have to eat alone anyway.

Please join me if that's okay with you.

What a sweetheart.

It looks like the same dog.

Dinner's ready. Come on.

Right.

I always eat alone, so I apologize for that lack of side dishes.

Gosh, please don't. It's been a while...

since I had someone else cook for me.

So...

you mentioned...

how your son found Boksil on a bridge.

May I ask which one it was?

Oh.

The one in Anshin-dong.

A while back, we lived there briefly.

Wasn't it around the time...

an incident happened...

in the neighborhood?

Yes, the Kang Duk Soo case.

How did you know that?

Then that boy...

was your son? Where is he right now?

Well...

An accident took him away from me.

Thank you for everything today.

I'm the one who's grateful for the meal.

- Get home safely then. - Sure. I'll get going.

(Moojin Bukbu Police Station)

Hey, Bong Yi.

Mister.

On the night of my accident.

Weren't you the one who took me to the hospital?

I did carry you on my back and ran to the hospital.

But I wasn't the one who found you.

I actually got a call.

Hello, this is Anshin-dong precinct.

I'm below the Anshin-dong bridge.

Oh, I see. Kid, did someone get hurt?

Please hurry up.

Hurry.

Is she okay? I'll carry her.

Are you okay?

- Doctor, she's badly injured. - Come this way.

Bring me some dry towels and a blanket.

- Call a surgeon too. - Yes, doctor.

(Gowon Middle School)

Your grandmother and I took the uniform to that school.

But no one stepped up and said it was him.

So we never found out who it was.

But why do you ask all of a sudden?

I met that kid's mother...

by coincidence.

Really?

Gosh, what a surprise.

But...

she told me her son is dead.

My goodness.

- Hello? - We found it.

We found the car with the license plate number 67D6264.

Okay. I'm sorry. I need to go.

(Moojin Bukbu Police Station)

(67D6264)

Do you know who he is?

He had no ID or cell phone, so we scanned his fingerprints.

Let me know once you find out who he is.

He got rid of the dashcam?

He didn't commit suicide. Someone made it seem like it.

The phone is turned off. You will be directed to voicemail.

Detective Shin, I'm going to send you a number.

Check it for me. I also need the base station.

Why did he hang something so personal...

when this wasn't even his car?

What's this?

So he kept two storage devices?

What a smart fellow.

He kept a backup just in case.

You were that kid?

Yes. I went to the police station and confirmed it.

After he found me in a near-death situation,

he called the police and ran with me on his back.

Your son saved my life.

I see.

My son...

never told me that.

So I never knew.

Thank you.

I should've thanked you earlier.

It would've been nicer if he were still alive...

so I could thank him myself.

My son...

My son was that kind of person.

He was such a kind kid.

I wonder why she put away all his photos.

She put away her son's photo that day as well.

I wonder why.

I feel like there might be a story to this.

I'm sure it was somewhere nearby.

There it is.

Something was written here.

I'm okay now.

I'm doing good.

I eat well.

It's all thanks to him.

"Him"?

He gave me the will to live, and I'm very grateful.

I'm talking about Doctor Sung Yo Han.

(Sung Yo Han...)

What...

Sung Yo Han was the guy who saved my life?

(Sung Yo Han, the murderer, lives here.)

How could a guy who saved my life...

and brought home and raised an injured dog...

kill my grandmother so brutally?

I mean...

You know what? He's a psychopath.

Maybe it was all an act. He acted like he was nice.

He probably acted like a kind kid.

Don't die.

Stay awake.

Please don't die.

Hang in there for your family.

Think about how sad your family will be if you die.

Your mom and dad.

Grandma.

No.

It wasn't an act.

He really meant it.

A psychopath can't be like that.

It doesn't make any sense.

As time went by, I slowly started to think...

that Dr. Sung might not be the murderer.

No. It's absurd.

It's crazy.

There's clear evidence.

Sung Yo Han tried to kill Ba Reum.

I'm sure he hit Ba Reum with a hammer.

If it wasn't Sung Yo Han,

who killed my grandmother?

Yes? The base station is...

at Yongja-dong?

Okay.

He got killed...

while trying to call me yesterday.

I think it's him.

Take a look.

Thank you.

(Student record)

(Name: Sung Yo Han)

Sung Yo Han?

The kid...

who treated my wound was Sung Yo Han.

He was a smart kid when he was young.

I don't know what happened to him.

I guess you never really know a person.

(Homeroom teacher's assessment: Seems a little obsessive)

It says here that he was obsessive. What does this mean?

I'm not sure. This kind of assessment isn't common.

Does this teacher still work here?

What is this?

He kept following Officer Jung?

This is near the bridge where Bong Yi was found.

What is this?

Who...

Hi. You were Sung Yo Han's homeroom teacher,

correct?

I'm busy.

The science class kids have an expo coming up.

Sorry, but I'm with the police.

Let me ask you just one thing.

Here. You wrote "obsessive". Do you remember that?

Yo Han said...

he thought someone kept following him.

He kept saying that repeatedly.

So he received counseling.

Yo Han was being followed when he was a child like I was.

The kids should be here soon. Please leave.

Thank you.

What are those mice for?

They're lab mice that the kids are going to use at the expo.

We fed one carbohydrate and the other protein.

Wait.

What did you say?

We're...

Ba Reum.

Why are you at the scenes of Kang Duk Soo's,

Lee Jae Shik's, and Kim Byung Tae's murders?

Ba Reum.

Was it you?

What?

We're...

Lab mice.

Lab mice.

Lab mice.

We're...

lab mice.

We are...

lab mice.