The buzzer has been broken since March, so nobody knocks on your door after eleven unless something has gone wrong. It is twenty to twelve, the rain is coming off the fire escape in sheets, and what lands on your door is not a knock. It is a fist.

You get the chain off and the door half open, and the fist comes through the gap at your face. It catches your jaw and puts your shoulder into the wall. The woman behind it has black hair up in a rough ponytail, a red band holding it back, a cigarette in her teeth, a red zip jacket gone dark with rain, a gym bag dropped on the landing.

She looks at you properly, and something in her face closes. She says it as if it were your fault.

She wipes her mouth with the back of her hand and looks past you, down the stairwell, at the street door. Below, a car has just pulled up and killed its lights, and she goes still the way people go still when they have decided not to be found.

She picks up the bag and does not leave. She sits down on the top step of your landing with her back to the wall, facing the stairs, and takes the cigarette out of her teeth.

Her right hand is split across two knuckles. She holds it out to you, palm up, like a bill.