Knock is the world's shortest horror story with only two sentences.
The last man on Earth sat alone in a room. There was a knock on the door.
it's twelve oh two. The lights are off. My sister is asleep. I feel alone.
Those two sentences gave me the chills.
I imagined a man sitting in the middle of a dark room with his head in his hands. The world outside is in ruins. There are no people around, not even dead bodies, no sign of any living creature at all; just rubble and stones tumbling down.
There is a knock on the door. The man lifts up his face and stares the door. His expression is one of fear.