The Blue Room’s Arithmetic

The house on Hemlock Lane had a way of swallowing sound. When we moved in, I thought it was just the old bones of the place—the creaking floorboards, the rattling pipes. But the quiet was different in the back addition, where my parents decided to knock down a wall and open up the kitchen. That’s when the knocking started.

I’m Delia, thirteen, sandwiched between my nine-year-old sister, Cora, and two-year-old Vi. We’ve been in this house for a year, and I’ve claimed the room at the top of the stairs. It used to be the master bedroom, but my parents took the smaller one next to it, saying they didn’t need the space. My room is always cold, even in July. My breath fogs in the winter mornings, and the floor feels like ice. My parents swear it was warm when they slept there, but I’ve learned to just pile on blankets.

It’s on Wednesdays that things get interesting. My mom takes Vi to her music class, and my dad drives Cora to her piano lesson, leaving me alone for about thirty minutes. That’s when the house truly wakes up. Footsteps pad down the hallway, pause outside my door, and then resume, back and forth. A gentle knock—three taps, a pause, two taps—as if someone is trying to get my attention. I’ve started counting the knocks, and they always spell out a pattern that doesn’t quite make sense, like a message in a code I can’t crack.

One Wednesday, I was lying on my bed, listening to a playlist on my phone, when the music suddenly cut off. I picked up my phone to see the screen black, but the songs started playing again from my speaker across the room—not my phone. The volume rose and fell, and my books on the shelf shuffled, sliding forward and then back. A small ceramic fox I’d bought at a yard sale tipped over and rolled to the edge, landing on the floor with a soft thud. I swear it was watching me.

The bathroom attached to my room had a will of its own. I’d hear the shower turn on when nobody was in there, water hissing against the tile. When I stepped in, the temperature would swing from scalding to freezing, sometimes in the same minute. I’d turn the knob to adjust, but it would resist, as if something had a grip on it. And the water would shut off abruptly just as I reached for the shampoo.

Vi’s toys were the most unnerving. They’d go off randomly, scattered throughout the house—a music box that played a tinny lullaby from her nursery, a plastic phone that beeped with someone else’s voice, a stuffed rabbit that said ‘I love you’ in a distorted pitch. My parents blamed dead batteries, but I knew better. It was as if the house was trying to communicate through the only language it had left.

And then there was my name. ‘Delia.’ I’d hear it whispered, called, sometimes shouted, from the hallway, from the backyard, from the basement. It came in my mother’s voice, my father’s, sometimes a child’s. I’d run to investigate, but always found emptiness. The calm that followed was the weirdest part—when I felt someone sit beside me on my bed, a weight depressing the mattress, I didn’t feel fear. I felt a warmth that contradicted the cold of the room, a sense that I was being watched over, not threatened.

One Wednesday, I decided to fight back. I set up my phone to record the hallway and my room. When the knocks came, I opened my door and shouted, ‘I know you’re there!’ The knocking stopped, and the house fell into a deep silence. Then, from downstairs, I heard Vi’s music box start playing her lullaby, and the shower turned on in the bathroom, the water running at full blast. I walked down the hall, and the doors to every room were open except for one—the door to the room my parents used to sleep in, now a storage space. I pushed it open, and the air hit me like a wall of cold. Inside, my parents had stacked boxes of old family photos; the ones on top were scattered on the floor, and they were of the couple who lived here before—the original owners, I guessed. Their faces were blurred, but I could see they had two kids, a boy and a girl, and they were standing in front of this house. The boy was pointing at the camera, and the girl was looking at something out of frame.

That night, I couldn’t sleep. I lay in my freezing room, listening to the house settle. At 3:13 AM, I heard footsteps on the stairs, heavy, deliberate. They stopped at my door, and the light from the hall disappeared, as if something was blocking it. I pulled the covers over my head, my heart pounding. Then I heard a voice, not my name, but something else: ‘Leave.’ It was a single word, deep and resonant, and it felt like it came from inside my chest. I peeked out, and the door was open, and in the hallway, I saw a silhouette of a tall figure, but it had no features. It raised a hand and pointed at me, then at the wall behind me. I turned to look, and on the wall, I saw water stains that hadn’t been there before, forming a pattern that looked like a blueprint of the house, with a red mark on the spot where I was standing.

I got up and walked to the wall, touching the mark. The temperature in the room spiked suddenly, and the stains spread, turning into a dark, wet patch that dripped down to the floor. The room began to smell of decay. I stumbled back, and the silhouette was gone. The knocking resumed, this time frantic, and my name was called in a whisper. I ran out of the house, into the yard, and stood shivering in the grass until my family came home.

I told my parents what happened, but they thought I had a nightmare. They had the walls checked, and the contractor found something behind the plaster—a metal box, sealed and rusted. Inside were letters, written by a woman who lived here decades ago. She spoke of her husband’s madness, of his obsession with the number thirteen, how he would knock in sequences of threes and twos to signal her. The last letter was dated the day he died, and it said, ‘He won’t let me leave. He’s in the walls. The blue room is his arithmetic.’ I realized the ‘blue room’ was my room—the master bedroom had walls painted a faded blue, and the pattern on my wall was the same as the one in the letter.

I don’t tell anyone, but I’ve started communicating back. On Wednesdays, I knock my own patterns: one, two, three, response from the walls: two, one. It’s a game, a conversation, a dance with something that might be a ghost or something else entirely. The cold has become a comfort, and the footsteps a soundtrack. Last Wednesday, I heard a child’s laugh in the hallway, and I smiled. I know I should be scared, but I’m not. I’ve figured out the arithmetic, and it’s simple: the dead don’t leave, they just get lonely. And I’m here, keeping them company.