The house was suffocatingly quiet by midnight. Da-eun stood at the top of the stairs, her bare feet pressing against the cold hardwood. Down the hall, the heavy oak door to In-ah’s home office was locked tight, but the brass key Da-eun had swiped from the kitchen counter felt heavy and sharp in her palm.

Beside her, Rora gave a silent nod, her eyes darting toward In-ah’s bedroom door at the end of the corridor. The low, rhythmic sound of their older sister’s breathing confirmed she was finally asleep, exhausted from a day of sheer panic.

Da-eun slipped down the hallway, inserted the key, and turned it. The lock gave a faint, metallic click.

Stepping inside, the room smelled of old paper and stale coffee. Da-eun approached the large metal filing cabinet in the corner, her flashlight illuminating the labels. Her fingers brushed past standard police records until she found a thick, unmarked manila folder tucked at the very back.

She opened it. Inside, there were no official police reports—only loose pages of personal handwritten journals belonging to In-ah, dating back seven years.

As Da-eun’s eyes scanned the faded ink of the first page, the present faded away, pulling her into her sister's memories from the summer before everything shattered.

Seven Years Ago – In-ah’s Journal

July 14th.

The heat this summer is unbearable, but nobody seems to care when we’re all together at the Park family’s estate. It’s become our unwritten rule: every Saturday, the four families gather. Look at us from the outside, and we make no sense. Min-jun, Seo-jun, and Tae-hyun are always dressed like they’re a minute away from a corporate board meeting. Min-jun is usually arguing with Woo-jin about property boundaries, while Seo-jun elegantly handles the grill, pretending he isn't listening.

Then there’s Do-hyun. He brought his tennis rackets today, trying to force everyone into a tournament. He managed to drag Woo-jin and Tae-hyun onto the grass court. Woo-jin plays dirty, laughing every time he hits a ball right at Tae-hyun’s feet, while Ha-yun sits on the sidelines with Chae-won, keeping score and shaking her head at their antics.

I’m sitting on the porch with my laptop, supposedly reviewing academy notes, but mostly I’m just watching them. We grew up in different worlds—money, law, athletics—but here, none of that matters. We’re a unit. A single, solid wall. If you asked me today, I’d say nothing could ever tear this group apart. We know each other’s worst habits, our deepest ambitions. We share everything.

But lately, there’s a strange undertone I can’t quite place. Min-jun and Woo-jin have been stepping away to take private calls. Yesterday, I saw Do-hyun arguing with Seo-jun behind the pool house, their voices hushed but furious. When they saw me walk by, they instantly smiled, their faces shifting back into the perfect, carefree expressions they always wear.

They think because I’m training to be an officer, I don't notice the shifts in the room. But I do. There is a tension building beneath the surface of these perfect weekends. A secret or a deal that they aren't letting the rest of us in on. I just hope whatever they’re hiding doesn't ruin the only home we’ve ever known.

Da-eun snapped the folder shut, her heart pounding against her ribs.

She looked up at Rora, who was reading over her shoulder. The journal entry didn't mention a crime, a scandal, or a betrayal. It showed the exact opposite—a time when the Kims, the Parks, the Jungs, and the Lees weren't enemies. They were a family.

Da-eun pulled out her phone, her fingers rapidly typing the encrypted code into the trio's chat to tell So-min what they had just uncovered.

In her darkened bedroom, So-min’s phone cast a pale glow over her face. Her thumbs flew across the screen as she decrypted Da-eun’s message about In-ah's journal.

[THE TRIO CHAT - ENCRYPTED]

So-min: They all used to hang out? Every weekend? Are you serious? My brother acts like he barely knows the Kims or the Parks.

Rora: In-ah wrote that they were like a single family. But she also noted that Min-jun, Seo-jun, and your brother Do-hyun were starting to hide things right before everything broke apart.

So-min: Guys... I think I found something too. Do-hyun fell asleep on the couch downstairs, and his jacket was hanging on the chair. I sneaked down to check his pockets.

Da-eun: What did you find?

So-min: A bank slip. A massive transfer of money from an anonymous offshore account into his personal savings. The date on the transfer? Seven years ago. The exact day after that text message mentioned.

Rora: Hush money? Or payment for something?

So-min: I don't know, but there’s more. I found an old, crumpled piece of paper in his wallet. It looks like a torn guest list from a high-end corporate gala the Kims hosted seven years ago. Our families' names are all circled in red ink, with a single note written at the bottom: "The truth stays here."

The chat went completely silent as the gravity of the realization settled over the three girls. Their families weren't just avoiding each other out of a petty grudge—they were actively keeping a massive secret together, bound by money and hidden threats.

Suddenly, a sharp noise echoed through Da-eun and Rora’s house.

The heavy creak of a floorboard sounded right outside In-ah’s office door.

Da-eun froze, her heart leaping into her throat as she looked at Rora. The shadow of a figure blocking the moonlight beneath the doorframe told them exactly what they didn't want to know: In-ah was awake.

Da-eun grabbed Rora’s wrist, her eyes wide as she pointed frantically toward the window.

The shadow beneath the door shifted. The doorknob began to turn with a slow, agonizing rattle.

With no time to think, Da-eun silently pushed open the glass window. Because the office was on the ground floor, the drop to the grass below was short. Rora scrambled through first, dropping quietly into the soft, damp soil of the garden. Da-eun snatched the manila folder, tucked it firmly under her arm, and climbed over the ledge just as the office door swung open behind them.

They crouched low behind a thick row of hydrangea bushes, pressing their backs against the cold brick wall of the house. Inside the room, the bright beam of a flashlight cut through the darkness, sweeping across the empty desk and the open window.

In-ah stepped up to the ledge, leaning out to scan the dark garden. Da-eun held her breath, her heart hammering so loudly she was certain her sister would hear it.

After a few excruciating seconds, In-ah muttered something under her breath, pulled the window shut, and locked it from the inside. The light in the office clicked off.

Rora let out a shaky breath, turning to Da-eun in the moonlight. "That was too close. We can't go back inside through the front door now—she'll know it was us."

Da-eun looked down at the folder in her hands, then out toward the quiet street. "Then we don't go back. Not yet. Pull out your phone. We need to tell So-min to meet us."