The footsteps upstairs

Source: an original fiction extract.

At closing time, Leon heard somebody walking above the shop. The ceiling creaked once, then twice, followed by the scrape of something heavy being dragged. He stopped counting the till. The upstairs storeroom had been locked since lunchtime, when the last delivery was put away. His manager had left an hour earlier. Outside, the shutters of the neighbouring shops were coming down in a sequence of metallic crashes. Leon waited until the street grew quiet. Another step crossed the ceiling, directly above his head.

He called towards the stairwell. There was no reply. The shop sold lamps, and only the smallest display remained switched on: six shaded lights casting separate pools along the counter. In the gaps between them, the room seemed longer than it did by day. Leon took the storeroom key from its hook. He remembered the delivery driver asking whether the stack of empty cartons should be moved away from the window. His manager had said they would deal with it tomorrow. At the time, Leon had been trying to find a missing receipt.

Halfway up the stairs, he heard the scrape again. It ended in a hollow thump. He stopped with his hand on the rail and listened to something roll across the floor. The sounds did not fit a person's movements now, but he could not decide what else they fitted. He called once more, louder. Then the light beneath the storeroom door disappeared. Leon took a step backwards before remembering that the room's window faced the road and a passing lorry could block its light. He made himself climb the remaining stairs.

When he opened the door, a strip of cold air struck his face. The window had blown inward against a pile of cartons. One box lay on its side, spilling wooden lamp bases across the boards. The tallest carton rocked in the draught, its bottom edge knocking the floor each time it tilted. Leon watched it make two slow taps. He pushed the window shut and fastened the catch. The room became still so abruptly that he could hear the small rattle of the key against his fingers.

Downstairs, he finished the till count and wrote a note about the window catch for his manager. He did not mention how long the stairs had seemed. Before leaving, he returned the lamps to their usual switches, extinguishing each pool of light in turn. A car passed outside and its reflection slid across the ceiling. Leon looked up automatically, then smiled at the empty boards. He checked the storeroom key, locked the front door and stood for a moment listening to the ordinary sounds of the street.

Consider the whole source. Analyse how the writer structures the text to build and resolve suspense about the noises upstairs. You could consider the order of information, changes in pace and focus, and the ending. Support your explanation with references to the source.