Back in his flat, the open windows had cooled the rooms, and the smell of the disinfectant had dispersed. He poured himself a glass of water and wandered into the sitting room, slipped off his gown and stood by the open window, letting the air breeze over his naked body. If he looked to the right he could see the portals of the British Museum, the Portland stone of its facade black with soot. He shut his eyes, imagining how it would have looked when first built, the cream edifice glistening as brightly as the Parthenon. A hundred years of London smog had made its mark. He ran his finger along the windowsill. Even now, in the summer, even after the Clean Air Act, fine grit layered the buildings, clouded the air.

A man cycled by and a lone taxi drove past, London’s early birds. Or late birds. Worshippers off to matins at St George’s. Revellers home from a night on the town. A man rounded the corner of Great Russell Street, sauntered into Bury Place. He wore a cap so his face was in the shade, but the walk was unmistakable. He stopped opposite, looked up. John stepped back from the window, heart racing. His hands grew clammy and the tumbler slipped from his grasp, hitting the lino with a thud, water spilling. John glanced down at the glass, then up and out of the window. The man had gone. John squeezed the curtain back, leaned to one side to see better. The man was nowhere to be seen. Neither right nor left nor straight ahead. How could he vanish into thin air?

He picked up the tumbler, fetched the floor cloth. He hadn’t slept well. That’s all it was. This time, he was imagining it. Besides, he hadn’t seen the man’s face. It could have been anyone. He imagined too much. Hallucinated. Flashbacks, the doctor called them. He threw the cloth onto the spill, watched as the heavy cotton absorbed the water, changing tone, texture. The man could have crossed the road. Of course. That would explain why he couldn’t be seen. He hadn’t disappeared at all. John couldn’t see anyone on his side of the street unless he hung out of the window.

Footsteps. The laboured thud as someone climbed the stairs. He froze. Had he closed the door? Or was it still on the latch, as he’d left it when he went to the lavatory? He ran towards it. It was shut, but he pulled the bolt across, just to be sure. Ear against the wood. Bob must have left the street door open again. The footsteps had stopped. Were they on his landing? Was the man outside? Was he listening, waiting, ready to break in? Surprise gave the greatest advantage. Ambush at dawn. John’s stomach griped. He looked towards the kitchen. Four strides, he’d be there, grab a knife, ready.