It starts with the small things, and this is the point: the small things are so small that you dismiss each one individually, and by the time the pattern is visible you have already been living with it for months.
The milk. I am precise about the milk. I buy a half-gallon on Sunday and I am the only person in the house and I know how much I use. By the second week in February I was going through a gallon, sometimes more. I thought: I'm drinking more coffee. I thought: I'm less careful than I imagined. I bought more milk. I did not think about it further.
The smell was harder to dismiss but I dismissed it anyway. A faint human smell in the bathroom in the mornings. Not unclean — not unwashed — just the smell of a body having occupied a space. I thought: my habits are changing. I thought: the ventilation in this old house is strange and unpredictable.
The crumbs on the kitchen counter. Always on the side by the refrigerator, which is not where I make my toast.
The single depression in the couch cushion on the left side, when I always sit on the right.
One evening I came home to find the thermostat set to 68. I keep it at 65. I have always kept it at 65. I set it back and thought: I must have bumped it.
The lock on my bedroom door was stiff. Stiffer than it had been. As if it had been engaged and disengaged many times in a short period.
Here is what I found: in the living room, on the west wall, there is a built-in bookcase. It runs floor to ceiling, eight feet wide. It has been there since I moved in four years ago and I have never had cause to pull it away from the wall. I pulled it away from the wall because the smell was strongest there, and because I had run out of other explanations.
Behind the bookcase was a door.
The door opened onto a room. The room was narrow — maybe six feet wide, twelve long — and had clearly been used, recently and continuously, as a living space. A sleeping bag on the floor, neatly rolled. A small camp lantern. Food, stored in a zip-lock bag: crackers, trail mix, beef jerky. A jug of water. A paperback book. And on the wall, above where someone had clearly been sleeping, several photographs.
Photographs of me.
Not surveillance photographs — not secret, lurking shots. Normal photographs. Photographs of me in my home: at the kitchen table, reading. On the couch, watching television. At my desk. The photographs were taken through interior doorways, from the hallway, through partially open doors. They were printed on normal paper from what appeared to be a home printer. Some of them I could date: I recognized the books on the table, the shows on the television.
There were thirty-seven photographs.
The most recent, by my estimation, was taken three days ago.
I called the police. They found nothing. No fingerprints — every surface wiped. The photographs had no identifying information. The sleeping bag was a common make. Whoever had been in the room had been very careful.
The detective told me to change my locks. I changed my locks.
That was six weeks ago.
Last week, I noticed the milk again.
I am trying to find the room. I have tapped every wall. I have measured every room and compared the measurements to the exterior. I have looked for spaces that don't add up. I have not found anything yet.
But the milk keeps disappearing. And last night, I woke at 3 AM to a sound I couldn't place — not loud, not alarming, just the specific sound of a person shifting their weight — and I lay in the dark and I listened, and the house was quiet, and I did not get up.
I did not get up because I don't know what I would find.
And I don't know what it would do when I found it.