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Chapter Four: Someone Was Watching

11:43 P.M. — Manhattan, New York

The first rule of cybersecurity was simple.

If something seemed wrong, it probably was.

The second rule was considerably less comforting.

Sometimes, the thing that seemed wrong was the only thing telling you the truth.

Rex Thompson stared at her laptop, chewing the inside of her cheek as another line of code appeared on the screen.

She should have been asleep.

She had work in the morning, a half-empty bottle of water beside her bed, and exactly zero reasons to be investigating a security anomaly after eleven at night.

Unfortunately, curiosity had always been her most expensive personality trait.

The legacy authentication request from yesterday had bothered her all day. She had reviewed the available metadata, checked the documentation, and confirmed that the service it referenced should have been retired months ago.

Yet the request existed.

Worse, it had been formatted to resemble legitimate system traffic.

Someone had either made a serious mistake or gone to considerable effort to make sure nobody noticed them.

Rex preferred mistakes. Mistakes were fixable.

She opened the archived documentation again and compared the request against the old authentication protocol. The sequence wasn't identical, but the structure was familiar. Whoever had created it understood the system well enough to imitate its habits.

Her fingers hovered above the keyboard.

"Okay," she whispered. "Show me what you're hiding."

She wasn't breaking into anything. She was working with the records she had legitimate access to, tracing references and comparing them against the historical documentation. She knew where the boundaries were.

Still, the more she looked, the less she liked what she found.

A transaction reference appeared in two separate archived records, both associated with the same legacy service. The dates were weeks apart. The originating credentials were masked, and the underlying financial activity remained inaccessible.

But the pattern was there.

Two records. One unusual authentication path. A system that should no longer have been active.

Rex saved her findings to an encrypted folder.

Then her screen flickered.

Once.

She froze.

The display returned to normal, and her laptop continued humming quietly on the desk.

"Don't start," she muttered at it.

She checked the system logs. Nothing immediately obvious. No unexpected process, no unfamiliar connection in the limited information available to her.

She was about to close the window when a notification appeared in the corner of the screen.

NEW DEVICE CONNECTED TO YOUR HOME NETWORK.

Rex stopped breathing.

She hadn't connected anything.

She opened her router's device list. Her phone. Her laptop. Her television. The smart speaker she regretted purchasing because it occasionally played music when nobody had asked it to.

All accounted for.

Except the new device.

Its identifier was incomplete, and the connection details were insufficient to establish what it was.

Her stomach tightened.

She refreshed the list.

The device disappeared.

Rex sat perfectly still.

There were innocent explanations. A neighbouring device might have been misidentified. A router might have refreshed its records incorrectly. Consumer networking equipment was hardly famous for its reliability.

She knew all of that.

She also knew that the timing was terrible.

Her phone lay beside her laptop. She picked it up and opened her messages.

For one ridiculous second, she considered texting Kane.

Hey, mysterious neighbour. Quick question. Do you know why an unidentified device just appeared on my network? Also, are you secretly a serial killer? Please answer both questions honestly.

She imagined his reply.

No.

Then, after a pause:

Which question?

Rex almost smiled.

Almost.

Instead, she secured her router's administration settings, saved the relevant logs, and disconnected the network while she reviewed the configuration.

Then she noticed something that made the room feel suddenly colder.

The device notification had appeared at 11:43 p.m.

The same minute she had reopened the archived authentication records.

Coincidence was possible.

But coincidence had just become the least comforting explanation.

12:06 A.M.

Three knocks sounded at her door.

Rex nearly dropped her phone.

She crossed the apartment, checking the peephole before opening the lock.

Kane stood outside.

His hair was dishevelled, and he wore a black T-shirt and dark trousers. Without his coat and carefully arranged public expression, he looked less like an untouchable stranger and more like a man who had been interrupted in the middle of something important.

His eyes moved over her face.

"Are you all right?"

Rex blinked.

"That's an unusually serious greeting from someone who usually communicates exclusively through sarcasm."

"You weren't answering your phone."

She glanced down at it.

Three missed calls. All from an unknown number.

Her humour vanished.

"I didn't hear it."

Kane noticed the change immediately.

"What happened?"

Rex hesitated.

She didn't know him. Not really. He was still a man whose past she couldn't verify and whose personal life seemed to have been scrubbed clean of ordinary details.

But he was also the person standing outside her door at midnight, asking if she was all right instead of asking what she had done.

"My network flagged an unidentified device," she said. "Then I got three calls from a blocked number."

His expression changed.

Not dramatically. Kane didn't seem like a man who gave much away.

But something in his eyes sharpened.

"When?"

"About twenty minutes ago."

"Did you answer?"

"No."

"Good."

Rex folded her arms.

"Would you care to explain why you said that like you were expecting me to tell you I had invited a stranger into my apartment?"

He glanced down the hallway.

"Can I come in?"

Every instinct she possessed told her to be careful.

Another part of her—the part that remembered him sitting on the floor beside her, holding a router steady without asking what was wrong—wanted to say yes.

She stepped aside.

"One suspicious comment and you're out."

"Understood."

He entered without touching anything, his gaze moving briefly over the room before returning to her.

Rex noticed the restraint. He didn't wander. He didn't start opening drawers or treating her home like an extension of his own.

"Show me," he said.

She brought him to the desk and turned the laptop towards him.

He studied the notification.

"Do you know what the device was?"

"No. The identifier was incomplete. I've saved the logs, but I can't establish what connected from that alone."

"Could someone have accessed your files?"

"I haven't found evidence of that."

"That's not what I asked."

She looked at him.

For the first time, there was something beneath his composure that looked almost like anger.

Not anger at her.

Anger at the possibility that someone had been inside her digital life without permission.

Rex felt an unexpected warmth in her chest.

Then she reminded herself that concern wasn't the same thing as trust.

"I don't know," she said honestly. "And I'm not going to pretend I do."

Kane nodded once.

"Good."

She frowned. "You have a very strange definition of reassurance."

"I'd rather you tell me the truth than give me an answer that makes me feel better."

The words settled between them.

Rex looked away first.

She wondered what it would be like to be around someone who meant that. Someone who didn't need her to make difficult things sound manageable.

The thought frightened her more than the unidentified device.

She closed the laptop.

"Do you think someone is watching me?"

Kane didn't answer immediately.

Outside, a siren wailed through the streets and faded into the distance.

"I think you should take this seriously," he said at last. "But we don't know what happened yet."

It wasn't comforting.

It was honest.

For some reason, that was worse.

12:19 A.M.

Kane stood beside the window while Rex examined the call history on her phone.

He had seen this kind of pattern before: an unexplained connection, an obscured identity, a person who suddenly found themselves at the centre of something they hadn't chosen.

He didn't know whether Rex's experience was connected to the investigation.

He couldn't afford to assume it was.

But when she had opened the door, he had noticed the way she held herself. Chin raised. Shoulders squared. A joke already waiting behind her teeth.

Fear, disguised as irritation.

He recognized it because he had spent most of his adult life disguising his own.

"Your network should remain disconnected until you've checked the configuration," he said. "And don't respond to those calls if they continue."

Rex looked up.

"Are you always this bossy?"

"Only when people are in danger."

Her expression softened for half a second.

Then the sarcasm returned.

"Must be exhausting, being everyone's handsome emergency contact."

Kane almost smiled.

"You're assuming you're on my emergency contact list."

"After tonight, I expect flowers and a commemorative plaque."

"Demanding."

"I have standards."

He looked at her then, really looked at her.

There were shadows beneath her eyes. Her hair was tied back carelessly, and one sleeve of her sweater had slipped over her hand.

She looked tired, and she was trying very hard not to let him see it.

He wanted to tell her that she didn't have to perform for him.

He wanted to tell her that she could be frightened without making it funny.

But those were things a man had to earn the right to say.

So he stayed quiet.

Rex glanced at the clock.

"You should go home."

"I am home."

"Your apartment is home. This is my apartment. You're a guest. Guests leave."

"Is that your professional opinion?"

"It's my exhausted opinion."

Kane moved towards the door.

At the threshold, he stopped.

"Rex."

She looked at him.

"Lock your door tonight."

Her smile disappeared.

Not because the instruction was unreasonable, but because of the way he said it.

As if he knew something he hadn't told her.

"Kane," she said slowly, "what aren't you telling me?"

For a moment, the hallway seemed to hold its breath.

He could have lied.

He had built an entire life around choosing the right lie at the right time.

Instead, he gave her the only truth he could offer without exposing a danger he didn't yet understand.

"I don't know enough yet."

Rex searched his face.

She wanted to believe him.

That was the problem.

She wanted to believe him because he had come when she was frightened, because he had listened without dismissing her, because for a few minutes his presence had made the apartment feel less empty.

She wanted to believe him, and she hated how quickly wanting could become a vulnerability.

"Goodnight, Kane."

"Goodnight."

He left.

She locked the door behind him.

Then she checked it twice.

12:31 A.M. — Apartment 19B

Kane waited until Rex's lights went out before taking his phone from his pocket.

He had three new messages from Luca.

The first contained a photograph of an archived financial record.

The second contained the same record, enlarged.

The third was a single sentence.

LUCA: Kane. You need to see this.

He opened the image.

The transaction reference matched the sequence Luca had found earlier that day. Beneath it was a timestamp and a system identifier associated with the retired authentication service.

Kane read it once.

Then again.

His blood went cold.

The record had been generated less than an hour ago.

And the originating device wasn't associated with Rex's work system.

It was registered to a private network inside their apartment building.

Kane slowly lowered the phone.

Across the hallway, behind a locked door, Rex Thompson was trying to convince herself that she was safe.

He looked towards the wall separating their apartments.

For the first time since meeting her, he wasn't wondering who she was.

He was wondering who had found her.

His phone vibrated again.

A message from an unknown number appeared on the screen.

STOP LOOKING FOR YOUR FATHER'S KILLER.

A second message followed.

OR YOUR NEIGHBOUR DIES NEXT.

Kane didn't move.

Outside, Manhattan glittered beneath the rain-soaked night, beautiful and indifferent, as though the city had never swallowed a secret it couldn't keep.

He read the messages again.

Then he called Luca.

When his friend answered, Kane's voice was quiet enough to be frightening.

"Find out who has access to this building."

"Why?"

Kane looked at the wall.

"Because someone just made Rex part of my investigation."

He ended the call.

And somewhere in the darkness beyond the windows, someone was already making their next move.