Have you ever scrolled through your smart lock's app logs?
I'm guessing no. Most people get a fingerprint lock for convenience — no more keys, one glance at your phone to confirm the door's shut, peace of mind. That unlock log page? Buried three menu layers deep. No one looks at it.
I never did either. Not until some mind-numbingly boring night in mid-July when I tapped through every single app on my phone.
My name's Chen Yu. Thirty-two. Renting a one-bedroom in Binjiang. The building went up in 2016 — not new, not exactly falling apart either. Building Three, Unit 304. No elevator. Three flights of stairs, all legs. The hallway walls were plastered with flyers for drain cleaning and scrap appliance pickup, layer over layer, some so yellowed you couldn't even read the numbers anymore.
Moving day was brutal. June in Binjiang hits like a steamer. I dragged two suitcases up to the third floor, sweat soaking a dark patch across the back of my T-shirt. Stopped at door 304, pulled out my phone, found the six-digit code the landlord, Sun, had sent me. Punched it in. The lock clicked open.
Sun was there that day too. Early forties, a clutch bag tucked under his arm. He stood off to the side watching me punch in the code. As I was hauling my luggage through the door, he suddenly said, "A girl rented this place before you. Lived here two years. Lease was up, she moved out." He said it fast, then dropped his eyes to his phone. At the time, I figured he was just being polite, giving me the place's history. Only later did it hit me — what landlord goes out of their way to mention the previous tenant to a new renter? If he hadn't said anything, I never would've asked. It felt like he needed to get those words out first.
The lock was called "Anju." Seven hundred-something yuan on Taobao. Sun installed it. Fingerprint, passcode, remote unlock — all the bells and whistles. He transferred admin access to me. I scanned my fingerprint. Just like that, I was moved in.
Worked fine.
About a month later — the exact day's fuzzy, a Wednesday, I think — I got off work early and collapsed on the couch, doom-scrolling. My WeChat feed was tapped out. Short videos had rotted my brain. My thumb was just wandering across the screen when somehow I landed in the Anju Smart app.
A little blue house icon. A lock in the top right corner.
The home screen had a big green circle: LOCKED. Battery at 83%. Below that, the latest log entry: fingerprint unlock, user: me, 7:02 PM, right when I'd gotten home.
I scrolled down.
The page loaded for a beat, then spat out more entries. 8:10 AM, left for work, fingerprint. 7:02 PM, home, fingerprint. Clean in between. Normal.
Scrolled further.
July 11, Tuesday. Unlock successful. 3:04:12 AM. Door closed. 3:04:14 AM.
A two-second gap.
I stared at that entry for a long time. Unlock successful. Then the door shut almost immediately. Two seconds. It takes at least three or four seconds just to open a door and pull it closed. This person — if it was a person — unlocked the door and never came in.
3:04 AM. I'd been living there over a month and had never scrolled this far back through the logs. I hadn't looked at any of them before.
I set my phone on the coffee table. Got up. Walked two laps around the room.
Maybe I did it myself. Got up to piss, the kitchen's right by the front door, my hand brushed against the scanner. No — the fingerprint reader needs an actual press. Walking past it won't trigger anything. And I don't open my door in the middle of the night. Even if I did, a normal person leaves the door open. The log would show a "door ajar" window. This entry had only two seconds.
I sat back down. Scrolled earlier.
July 10: unlock at 3:04:11 AM, close at 3:04:13 AM.
July 9: unlock at 3:04:10 AM, close at 3:04:12 AM.
July 8: same thing.
I powered through two weeks of logs. Every single day. The time fluctuated between 3:04:05 AM and 3:04:15 AM, but always within the 3:04 minute. Never outside that window.
My palms started sweating. Not fear, exactly. Just this quiet, creeping damp that seeped out of the skin. I flipped my phone facedown on the table and stared at the ceiling for a while.
Then I remembered the camera.
I'd installed it my second day there. A cheap Xiaomi security camera, ninety-nine yuan on Taobao. Perched on top of the air conditioner, aimed at the front door. Living alone — figured it couldn't hurt.
Opening the camera app, I was still telling myself to calm down. It was probably a system glitch. Smart devices. Timestamp errors. Happens all the time.
The footage loaded. I dragged the slider to 3:00 AM and hunched over my phone.
Black-and-white. Infrared night vision. The AC unit's angle covered most of the living room and the full front door. Furniture edges glowed with pale, blurry outlines.
The seconds ticked. 3:02. 3:03.
3:04 came and went.
The front door didn't budge.
I checked the timestamp again. The camera's timecode matched the lock logs perfectly. The lock said the door opened. The footage showed the door not even quivering.
I watched five times. The handle didn't turn. The door didn't move. The keychain hanging on the frame didn't sway. The entire living room was as still as a screenshot.
I put the phone down. Looked at the front door. Brownish-red. Heavy steel. Walked over. Touched it. Cold. Deadbolted. Fine. Tested it with my fingerprint — opened normally, closed normally. The app immediately popped a new entry. Five seconds between open and close. That was me pulling it open, leaning out for a look, then shutting it.
Everything normal.
Except those dozen-plus entries at 3:04 AM. Every one of them with a two-second gap.
I didn't sleep well that night. Couldn't even say what I was afraid of. The thing that really keeps you up isn't ghosts. It's the things that don't add up.
The next day at lunch, I called Anju Smart's customer service.
A guy picked up. Young voice. Faint southern accent. Employee number 0317. I wrote it down later in a notebook — people do weird things when they're scared, and memorizing support ticket numbers is apparently one of them.
I told him what was happening. Unlock logs at 3:04 AM. I was asleep. No one else in the apartment.
He asked for my device ID. Keyboard clattered for a bit.
"Sir, our backend does show a daily unlock log at 3:04 AM. Fingerprint unlock. Finger ID 01. The open-to-close gap is about one to two seconds."
My fingerprint was ID 01. The first one registered. The only one.
I said I was absolutely certain I'd been asleep. And no normal human unlocks a door and closes it in one second.
Silence on the line. More typing.
"It could be a system time calibration issue. Network syncing sometimes causes timestamp drift."
"Then why the exact same time every single day? Shouldn't a glitch at least have some variation?"
He went quiet again.
"Do you sleepwalk?"
"No."
"Has anyone else's fingerprint been registered?"
"I live alone. I've changed the passcode twice."
A long silence. So long I had to say hello again.
When he finally spoke, his voice was noticeably slower, like he was thinking and talking at the same time: "Our fingerprint module uses semiconductor tech. It requires a living fingerprint — conductive, with body heat — pressed against the sensor before it'll generate a log. In principle, the system cannot produce false positives."
"So?"
"So either a finger was pressed against it, or—" He stopped abruptly. I heard him inhale. "Sir, your device ID — this is the third call I've taken today. All same residential complex." His voice dropped low, like he was afraid someone in the next cubicle might hear. "The first two also had unlock logs around 3 AM. Fingerprint unlocks."
"Same complex?"
"Yeah. But I checked the backend—" He cut himself off again. Like he realized he'd said too much. "It's nothing. Try doing a factory reset. Re-register your fingerprint. If the issue persists..."
He didn't finish. I heard another voice in the background, someone asking him something. He rushed out a "thank you for calling" and hung up.
I sat at my desk for a long time.
A customer service rep. Said he'd taken three calls from the same complex today. All about 3 AM unlocks. What was he about to say? What did he see in the backend?
Something he was afraid to tell me.
I called the landlord.
Sun. Met him once on signing day. Early forties, clutch bag under his arm. Had that slick rental-industry way of talking — could field anything without really answering. But that day, he'd brought up the previous tenant on his own. Looking back, that alone was off.
"Sun, the previous tenant in 304 — did she say anything when she moved out?"
"Problems? No problems. The unit's in great shape."
"What about the lock? Anything weird with the lock?"
"Brand new lock. I installed it right before you moved in. Less than six months old."
"Did she leave anything behind?"
Sun paused.
"You run into something?"
I hesitated. Then told him. The 3:04 AM unlock logs.
His reaction was stranger than anything I'd expected. He didn't act surprised. Didn't ask follow-ups. Just grunted once and said I should try changing the lock. "Get a new one." He said it with absolute certainty — like he'd always known the old one was useless but needed me to say it. Then he said he was busy and hung up.
That evening, I called a locksmith named Old Zhou. Twenty years in the trade. He'd handled every lock there was. When he went to remove the old one, he twisted for a while and muttered, "Stuck in there pretty tight." As the lock body came off the door, he stopped.
"You've got something jammed in the wall here."
I leaned in. Behind the lock cavity, there was a small hollow in the wall stuffed with paper. Old Zhou fished it out with a screwdriver — a shopping receipt, folded over and over. I unfolded it. The print had faded. All I could read was the date at the bottom: last October.
"Probably the previous tenant," Old Zhou said. "Some people stash things behind door locks. Superstition. To ward off bad luck."
I flipped the receipt over. There were words on the back. Written in fountain pen. Light strokes, like whoever wrote it was afraid someone might see:
Mom, the lock's installed. Now you can see me come home every day on your phone. Don't worry.
Delicate handwriting. I folded it and put it in my pocket.
I had him check the old lock for anything wrong. He opened it up, examined the circuit board. Said the build quality was decent.
"Any chance it could unlock itself?"
"How?" He laughed. "It's a fingerprint lock. Needs a fingerprint. Conductive. Body heat. Pressed against the sensor." He repeated "needs a fingerprint" several times, like he was worried I wouldn't believe him.
I believed him. But I believed even more that I hadn't gotten out of bed at 3 AM.
The new lock was called "Zhitong." Twice the price. Old Zhou installed it, tested it three times, took his payment, and left.
I didn't sleep that night. Not entirely out of fear — I wanted to verify. Midnight. One. Two. At 2:50, I heard it.
Coming from the front door. Very faint. Like skin brushing across a wood floor. Right behind the door, on the entryway tiles.
My body locked up.
It lasted three or four seconds. Then stopped.
I stared at the door.
Three o'clock. Nothing.
3:01. 3:02. 3:03. I was counting down in my head.
3:04.
Beep — a short, soft chime. In a living room so silent I could hear my own heartbeat, that beep squeezed something in my chest.
Then I heard it. The deadbolt sliding out of the strike plate. Tiny sound. But unmistakable.
The door was unlocked.
The door didn't move. But the lock had opened.
About two seconds later, another soft sound — the bolt clicking back in.
The whole thing took maybe a little over two seconds. If I hadn't been lying there waiting for it, I'd never have noticed.
I grabbed my phone. Opened the Zhitong app. The screen glow hit my face. The log was there, quietly waiting: fingerprint unlock. Unlock successful. 3:04:09 AM. Door closed. 3:04:11 AM.
New lock. Old log format. The time was still there.
I walked to the door. Pressed my ear against it. The security door was thick, steel. Cold. I stayed like that a long time. Couldn't hear anything. But I also felt like I could — a sound so thin it barely qualified as sound. Like someone was standing on the other side. Ear pressed to the door.
Face to face with me. Three centimeters of steel between us.
When I pulled back, my heartbeat was pounding in my ears so loud I couldn't tell if what I'd heard was real or something my own brain had manufactured.
That night, I thought of the fitness band. I wore a Xiaomi band to sleep. It tracked sleep data. Truth was, I'd thought of it before. I just hadn't dared check.
The band's app had a log entry waiting: 3:03:48 AM — body movement spike. 3:04:09 AM — heart rate hit 127. 3:04:35 AM — started dropping back down.
The eye-open record showed my eyes suddenly opened at 3:03 AM. Lasted about a minute.
The heart rate peak came about one second after the lock log's unlock time. Which meant my heart only started racing the moment the lock opened. Like my body knew what was happening before my brain did.
I had been awake in that moment. But my mind was a blank.
The next day, I called Sun.
It rang seven times before he picked up.
"Sun. That woman in 304 — she didn't move out, did she?"
A long silence on the line.
He sighed.
"How'd you figure it out?"
I didn't answer. "How did she die?"
More silence.
"Sudden death," he said. "Coroner said heart failure. Passed at night. Door was deadbolted from inside. Ten days before anyone smelled it and called the police."
"What time?"
He paused. "I never asked for that level of detail. The coroner estimated early morning. Couldn't narrow it down. Just a rough window."
"And after?"
"I swapped the lock. Repainted the walls." His voice suddenly sounded exhausted. "Chen, it's not that I wanted to hide it. If word gets out about something like this, the unit's dead weight."
"Before you changed the lock — was there anything wrong with it?"
He stopped.
I told him about the unlock logs.
Silence on the other end. The kind where you check to see if they hung up.
"You changed the lock too, didn't you?"
"Yeah. Same thing."
His voice started shaking.
"I changed the lock. You changed yours. But the log's still there?"
I said yes.
He hung up.
I sat in the living room thinking. Lock changed. Records still there. The previous tenant dying inside — that was scary, sure, but at least there was an explanation. Heart failure. Bad luck. But a new lock with the same records? No explanation for that.
My fingers found their way into my pocket. Touched the folded receipt. I pulled it out and read it again. Mom, the lock's installed. Now you can see me come home every day on your phone. Don't worry.
Every night at 3:04 AM, she "unlocked the door" so her mom could see it on her phone.
The thought went in like a needle.
I remembered the customer service rep — three calls from the same complex today. If it wasn't just 304, then maybe it wasn't just Xiao Liang in this building either. But I couldn't think that far yet. I had to deal with what was right in front of me.
I turned on every light in the apartment. Kitchen. Bathroom. All of them. Sat on the couch. Waited.
Eleven. Midnight. One. Two.
2:50. There it was again. The faint scraping from the front door.
Three o'clock.
3:04.
Beep. Unlocked. Locked again. Exactly like the night before.
This time, I didn't walk up and press my ear to it. I stood in the middle of the living room. Two meters from the door. Eyes fixed. Not blinking.
I saw it clearly. The inner handle didn't move. No sound from outside. The entire door was perfectly still.
But the lock opened.
Then closed.
In that moment, I knew: it wasn't the lock. The first one wasn't defective. Neither was the replacement. The sensors were working. The fingerprint module was working. Something had pressed its finger against the scanner on the outside handle. The lock recognized it. The deadbolt slid open. And in the next second, whatever it was pushed the door back and locked it again. Physically, the door had never actually swung open. Only the bolt had moved.
The wad of paper Old Zhou found in the wall floated into my head. It wasn't the lock. It was the door. Or rather, it was this position — any lock installed here, no matter the brand, would record that fingerprint log. That final lock Xiao Liang had confirmed before she died. Somehow, that action had been etched into this spot.
Over the next few days, I did everything I could think of.
Went to the property management office for security footage. A woman named He didn't even look up. Told me the cameras were down. "Since when?" "Last month." "When will they be fixed?" She finally raised her eyes: "Did you lose something?"
I didn't answer. She looked at me for a few seconds. Her glance swept my face, like she was weighing something. Then she lowered her head and went back to writing in her notebook. While she wrote, she casually asked what floor and unit.
Building Three, 304.
Her writing hand paused. Just a beat. Then kept going. But I saw it. She didn't look up. Said, "Third floor, huh. The cameras are definitely out. The hallway lights on that landing keep blowing out too, don't they? Third floor wiring's unstable. Multiple repair requests. Technician went to look but couldn't find anything."
"When will it be fixed?"
"Hard to say. Waiting on parts." She flipped a page in her notebook. The motion was natural. But she flipped it too fast. Turned over a page with half-written lines still on it.
I said thanks and left. At the door, I glanced back. She was staring at the computer screen in front of her. From the side, I could see the screen was locked. She was just staring at a dark monitor.
I searched the building's address online. Real estate listings. Delivery station addresses. Neighborhood committee notices. Nothing special. Added three search terms: "Building Three," "304," "death."
The third result was a local forum post. Last November. Saying a woman in a Binjiang complex was found deceased in her apartment after several days.
A short post. Twenty-five years old. Lived alone. Discovered after ten days. A neighbor smelled something and called the police. Foul play ruled out. Details withheld.
There were comments. One I read over and over: "The door was deadbolted from the inside. Locked tight. Police had to call a locksmith to get in. I heard the coroner estimated time of death in the early morning hours. Sometime between three and four."
Between three and four.
3:04 AM.
I screenshotted it.
Then sat in the darkening living room.
That female tenant. Sun said she lived there two years. Lease was up. Moved out.
She never moved out.
She died in this apartment. Between three and four in the morning. Most likely at 3:04. And after she died, her door lock unlocked itself at that exact time every night. Opened once. Closed once. Replacing the lock didn't help. It wasn't the lock recording. It was the room.
The day I finally got the dead tenant's family's number from Sun, I put off calling for hours.
A middle-aged woman answered. Voice a little hoarse. I said I was the current tenant of 304. No ill intentions. Just wanted to ask about something. She was guarded, but she listened. In the background, a TV was playing. Soap opera in the living room. Totally mundane.
Discussing something like this in such an ordinary setting — it made everything feel even stranger.
"Auntie, did Xiao Liang ever sleepwalk?"
A long pause.
"Not exactly sleepwalking," she said. "She'd just get up sometimes in the middle of the night. Walk to the door. Touch the lock. Go back to bed. She'd done it since she was little. New environments made her uneasy. I bought her that lock so she could see the logs on her phone and I could too. She told me it made her feel safe. It made me feel safe."
Something clenched in my chest.
I told her about the lock logs. No embellishments. No horror. Just the facts. 3:04 AM. Every day.
The other end went dead silent. Then — breathing. Suppressed. Very quiet.
After a long time, she spoke.
"That lock. I was the one who bought it for her."
"She lived alone. I was scared for her safety. I had the app on my phone too. After she passed, I couldn't open it for a long time. Then one day I did. The logs were still there. Every day. 3:04 AM. Same as when she was alive."
Her voice broke. The sound of a sniff.
"I tried," she said. "I had a locksmith come check. He said the lock was fine. I swapped the cylinder. The logs were still there. I even brought someone in to look. They told me it wasn't the lock. She just hadn't left yet. I didn't believe them. I deleted the app and reinstalled it. Still there. Deleted it again." She paused. "You know what I did in the end? Deleted everything. Never installed it again."
"Auntie, have you thought about bringing someone in again?"
"Bring someone in for what? That's my daughter." Her voice hardened. "She doesn't open the door. She just touches the lock. She's scared on the other side too. Touching the lock makes her feel safe. You want me to have someone drive her away?"
Those words hit me like a slap. I opened my mouth. Nothing came out.
She hung up.
I stood there with the phone in my hand for a long time. The wall clock in the living room ticked loudly. Click. Click.
She'd bought that lock. Her daughter's lock. For safety. Registered her fingerprint. ID 01. Every night at 3 AM, she got up and walked to the door. Touched the lock to make sure it was secure. Went back to sleep. After she died, the habit remained. Not in the lock — I'd seen it with my own eyes when Old Zhou took it apart. No defect. Nothing abnormal. It was in the door. The wall. This space.
It wasn't the lock.
That thought had become a needle in my brain. I couldn't pull it out.
After that, I started taping the door shut every night before bed. A tiny strip of clear tape across the seam. Thin. Easy to miss. One end on the door. One end on the frame. If the door opened — even a centimeter — the tape would break.
Every morning, the tape was intact.
But the app logs were still there. Every day. 3:04 AM. Unlock. Two seconds later. Lock.
It confirmed one thing: whatever was out there only triggered the bolt sensor. The fingerprint module recognized her. The deadbolt slid back. She never pulled the door. Just pushed the bolt back in. The door never physically moved at any point in the process. A spirit doesn't push doors open. She only ever touched it.
I thought about moving. Checked my bank balance. Calculated the deposit penalty. Browsed rental apps for hours. Rent in Binjiang had gone up since I signed my lease. Turned off my phone. Stared at the ceiling.
Fear was one thing. Money was another.
But honestly, it wasn't just the money. That receipt. I kept it in my drawer. Sometimes I took it out and looked at it. Thought about Xiao Liang's handwriting on the back. Mom, the lock's installed. Now you can see me come home every day on your phone. Don't worry.
At the end of the month, there was a company team-building dinner. I drank. A coworker dropped me off at the complex gate after midnight. Light rain was falling. I'd grabbed a clear convenience store umbrella. Stepped through wet tiles to Building Three.
The hallway lights were out again.
I didn't turn on my phone's flashlight. Just followed the wall up. By the third month, I could navigate these stairs in the dark. The steps had shifted — some of them, anyway — and my feet had memorized where.
On the third-floor landing, I stopped.
The hallway was dark. Somewhere at the far end, a dim light seeped from under the stairwell door. Just enough to outline the front of the door.
A figure was standing there.
Facing my door. Not leaning. Not moving. Just standing. Back to me. In the half-dark, the outline was blurry. A woman. Slim. Long hair.
I didn't scream. Didn't run. My feet just wouldn't move.
She was standing about half a step from the door. Her right hand was raised. The angle was exactly what you'd do if you were pressing a finger to a lock scanner.
The rain outside had stopped. The stairwell was silent. She stood there. I stood here. Two people who, by every law of nature, should not be sharing the same space.
I don't know how long it lasted. Maybe ten seconds. Maybe a minute. Then the light from the stairwell door flickered once. Just a blink of darkness.
When it came back, she was gone.
The hallway was empty.
I walked up to the door. My hands were shaking. Put my finger on the scanner. Beep. The lock slipped open. I pushed the door and walked in.
In the dark living room, I didn't turn on the lights. Leaned against the inside of the door. Breathed.
The tape was intact.
I looked at my phone. 3:04 AM.
The new log was already there. Fingerprint unlock. 3:04:11 AM.
After that night, something shifted.
Not the fear. The fear was always there. What changed was the nature of it.
Before, I'd been afraid of an unknown something. Now I'd seen her. Not a vague shadow or a flicker in the corner of my eye. A person. A woman. Xiao Liang. Just standing there. Doing what she'd done every night while she was alive. Touching the lock. Making sure the door was secure.
It was terrifying. But it was also... something else.
A few days later, I made another call. Not to her mom this time. To a friend of a friend who knew something about this kind of thing — a folk practice that was more custom than religion. I told him the situation. He listened, asked a few questions, then went quiet.
"Can you do something about it?" I asked.
"Depends what you mean by 'something,'" he said. "If you're asking whether I can make her leave — there are ways. But." He paused. "That's someone's kid, man. Someone's daughter. She's not hurting anyone. She's just touching a lock."
His words echoed what her mother had said.
"I'm not calling it off unless you really want me to. But from what you've told me — she died young. Died scared. Every night since, she's been checking her lock. You can chase her away, or you can let her keep doing it. Up to you."
I didn't answer right away. Thought about the receipt. Mom, the lock's installed. Now you can see me come home every day.
"Let it be," I said.
"Thought you'd say that."
I still live here.
Some nights, if I'm still awake when 3 AM rolls around, I'll sit on the couch in the dark and wait. Not with the lights on anymore. Not scared. Just... waiting.
At 3:04, the lock beeps. Soft. Familiar now. The bolt slides. Pauses. Slides back.
I've gotten used to it. It's become part of the apartment's rhythm. Like a radiator ticking in winter. Like an old pipe groaning in the walls.
Sometimes I think about that receipt folded up in my drawer. About a girl who bought a smart lock so her mom could see her come home. About a mom who kept the app on her phone even after her daughter was gone, watching a ghost check her door every night.
And about myself. Lying in the same apartment. Heart pounding at 127 beats a minute while my body knew something my brain didn't.
I think about a lot of things.
Once I messaged the mom. Just a short text. Said I'd found a receipt behind the lock. Asked if she wanted it.
It took her two days to respond.
Her reply was one line: Keep it safe. Thank you.
I still live here.
The tape on the door is still intact every morning. The log is still there. 3:04 AM. Unlock. Lock. Every day.
Some things don't need fixing.
Some things just are.