SEOUL — 2:17 A.M.
Han Seo-yeon woke because her phone vibrated.
Once.
Then again.
She reached for it without opening her eyes.
The screen lit up the dark bedroom.
1 NEW MESSAGE
From:
Kang Min-jae
Seo-yeon immediately sat up.
Min-jae never texted her at 2:17 in the morning.
Not once in the three years she'd known him.
She opened the message.
Don't come looking for me.
Seo-yeon stared.
Another message appeared.
Whatever you hear tomorrow, don't believe it.
Her heart began beating faster.
She typed.
Where are you?
No reply.
She typed again.
Min-jae?
Nothing.
Then—
typing...
The three dots appeared.
Disappeared.
Appeared again.
Finally, one last message arrived.
If I disappear, find the blue door.
Seo-yeon's fingers went cold.
She called him.
The phone rang.
Once.
Twice.
Three times.
Then—
The number you are calling is unavailable.
Seo-yeon stared at the screen.
Something was wrong.
Something was very wrong.
She got out of bed.
INT. SEO-YEON'S APARTMENT — CONTINUOUS
Seo-yeon pulled on a hoodie and grabbed her bag.
Before leaving, she looked at Min-jae's last message again.
Find the blue door.
She knew exactly what he meant.
At least—
she thought she did.
Three months earlier, Min-jae had shown her an abandoned building near the old Seoul railway district.
There was a blue metal door at the back.
He had laughed when she'd asked why it was there.
MIN-JAE
Every creepy place needs a creepy door.
SEO-YEON
That's not an explanation.
MIN-JAE
It wasn't supposed to be.
She had forgotten about it.
Until tonight.
Seo-yeon ran downstairs.
EXT. SEOUL STREET — 2:41 A.M.
The city is almost silent.
Streetlights reflect off wet pavement.
Seo-yeon walks quickly.
She keeps checking her phone.
No new messages.
She calls Min-jae again.
Nothing.
Then her phone vibrates.
She freezes.
Not a message.
A notification.
LOCATION SHARING: KANG MIN-JAE
Seo-yeon opens it.
A blue dot appears.
Her face changes.
The location is moving.
Fast.
Then suddenly—
it stops.
At the old railway district.
Seo-yeon starts running.
EXT. ABANDONED RAILWAY BUILDING — 3:06 A.M.
Seo-yeon stands outside.
The building looks abandoned.
No lights.
No cars.
No people.
She walks around the side.
There it is.
The blue door.
She reaches for the handle.
Locked.
She checks her phone.
The location dot is directly on the other side.
She knocks.
SEO-YEON
Min-jae?
Nothing.
She knocks again.
SEO-YEON
Min-jae, it's me.
A sound comes from inside.
Something falls.
Seo-yeon steps back.
Then—
the blue door slowly opens.
Not from the inside.
From the wind.
She stares into the darkness.
INT. ABANDONED BUILDING — CONTINUOUS
Seo-yeon turns on her phone flashlight.
Dust.
Old boxes.
Broken furniture.
Nothing else.
Then she sees something on the floor.
A backpack.
Min-jae's backpack.
She rushes toward it.
SEO-YEON
Min-jae?
She opens it.
His wallet.
His keys.
His notebook.
And his phone.
Seo-yeon's stomach drops.
If his phone is here—
who sent the messages?
She picks it up.
The screen turns on.
One application is open.
A recording.
She presses play.
Min-jae's voice fills the room.
MIN-JAE'S RECORDING
If you're hearing this...
I'm probably already gone.
Seo-yeon stops breathing.
MIN-JAE'S RECORDING
Seo-yeon, there's something I never told you.
The recording suddenly cuts.
Seo-yeon stares at the phone.
Then—
she hears footsteps behind her.
She turns.
Nobody.
The footsteps stop.
Seo-yeon backs toward the blue door.
Her phone vibrates.
A new message.
From Min-jae's number.
You shouldn't have opened the door.
Seo-yeon looks toward the darkness.
Then another message arrives.
Now they know you're here too.
~THREE YEARS EARLIER~
INT. UNIVERSITY CAFETERIA — DAY
Min-jae laughs.
Seo-yeon throws a napkin at him.
SEO-YEON
You are the most irritating person I've ever met.
MIN-JAE
And yet you eat lunch with me every day.
SEO-YEON
Because you steal my food.
MIN-JAE
That's friendship.
Seo-yeon rolls her eyes.
Across the cafeteria, another student watches them.
Lee Ji-won.
Quiet.
Observant.
She walks over.
JI-WON
You two are always together.
SEO-YEON
Unfortunately.
MIN-JAE
She'd miss me if I disappeared.
Seo-yeon laughs.
SEO-YEON
I'd celebrate.
Min-jae smiles.
None of them know yet—
that one day, those words will hurt.
Over the next three years, the three become inseparable.
Seo-yeon.
Min-jae.
Ji-won.
They study together.
Eat together.
Argue.
Laugh.
Share secrets.
Min-jae is the loud one.
Seo-yeon is the practical one.
Ji-won is the quiet one who notices everything.
But there is one thing none of them know.
Ji-won keeps a second phone.
And every night—
at exactly 2:17 A.M.
she receives a message.
The sender is always the same.
Unknown Number.
The messages contain only one sentence.
How much longer can you keep pretending?
~PRESENT DAY~
INT. SEO-YEON'S APARTMENT — MORNING
Police cars are outside.
Min-jae is officially missing.
Detective Choi Hyun-woo sits across from Seo-yeon.
DETECTIVE CHOI
When was the last time you saw him?
Seo-yeon hesitates.
SEO-YEON
Yesterday afternoon.
DETECTIVE CHOI
Did he seem frightened?
She remembers the message.
Don't come looking for me.
SEO-YEON
No.
A lie.
Detective Choi studies her.
DETECTIVE CHOI
Did he tell you anything unusual?
Seo-yeon looks down.
SEO-YEON
No.
Another lie.
Detective Choi stands.
DETECTIVE CHOI
If you remember anything, call me.
He leaves.
Seo-yeon immediately checks her phone.
A message.
Unknown number.
Good.
Another.
You didn't tell him about the blue door.
Seo-yeon's blood runs cold.
She looks toward the window.
Across the street—
a person is standing beneath an umbrella.
Watching her apartment.
She blinks.
They're gone.
INT. UNIVERSITY LIBRARY — AFTERNOON
Seo-yeon finds Ji-won.
SEO-YEON
You knew about the blue door.
Ji-won freezes.
JI-WON
What?
SEO-YEON
Don't lie to me.
Ji-won closes her book.
JI-WON
Where did you hear about it?
SEO-YEON
Min-jae told me.
Ji-won's expression changes.
JI-WON
He wasn't supposed to tell you.
Silence.
Seo-yeon stares at her.
SEO-YEON
What wasn't he supposed to tell me?
Ji-won looks around.
JI-WON
Not here.
She stands.
JI-WON
Come with me.
INT. UNIVERSITY BASEMENT — EVENING
Ji-won unlocks an old storage room.
Inside are boxes.
Photographs.
Newspapers.
Old university records.
Seo-yeon looks around.
SEO-YEON
What is this?
Ji-won doesn't answer.
She walks to a box.
Opens it.
Inside—
three photographs.
Seo-yeon picks one up.
It shows Min-jae.
But he's much younger.
Beside him stands a fourth person.
A girl.
Seo-yeon doesn't recognize her.
SEO-YEON
Who is she?
Ji-won whispers—
JI-WON
Yoon Ha-eun.
SEO-YEON
I've never heard that name.
JI-WON
Because everyone agreed to forget it.
Seo-yeon looks at her.
SEO-YEON
Why?
Ji-won finally looks directly at her.
JI-WON
Because Ha-eun disappeared three years ago.
Seo-yeon's hands tighten around the photograph.
SEO-YEON
Three years ago?
Ji-won nods.
JI-WON
The same week Min-jae met you.
Silence.
Seo-yeon slowly looks at the photograph again.
Min-jae is smiling.
But Ha-eun isn't.
She's staring directly at the camera.
Almost as though she knows someone will look at the photograph years later.
That night, Seo-yeon listens to Min-jae's recording again.
This time, she notices something.
Behind his voice—
a faint sound.
A clock.
Tick.
Tick.
Tick.
Then a train horn.
Seo-yeon freezes.
She searches old railway schedules.
One train passes the abandoned district every night at exactly 2:17 A.M.
The same time Min-jae's messages arrived.
She realizes something.
2:17 isn't when he disappeared.
It is a time marker.
She opens his notebook.
On the last page is a list.
Three names.
Yoon Ha-eun.
Kang Min-jae.
Han Seo-yeon.
Her own name has been added recently.
Below the three names is one sentence.
Only one of them remembers what happened.
Seo-yeon whispers—
SEO-YEON
What happened?
Her phone rings.
Ji-won.
Seo-yeon answers.
SEO-YEON
Ji-won?
Silence.
Then Ji-won's voice.
Barely audible.
JI-WON
Seo-yeon...
Don't trust me.
The call ends.
Seo-yeon stands completely still.
Her phone rings again.
Unknown number.
She answers.
UNKNOWN VOICE
Now you're finally asking the right questions.
SEO-YEON
Who are you?
A pause.
UNKNOWN VOICE
Ask yourself why you don't remember Ha-eun.
The call ends.
Seo-yeon looks at the photograph.
At Ha-eun's face.
And for the first time—
something inside her mind moves.
A memory.
A blue door.
Rain.
Someone screaming her name.
And a fourth person standing beside her.
A memory she has spent three years forgetting.
SEO-YEON
No...
She drops the photograph.
Because suddenly—
she remembers.
She had been there the night Ha-eun disappeared.
And Min-jae had been there too.
But Ji-won had not been.
At least—
that's what she remembers.
The phone vibrates.
One final message appears.
Now remember what you did.