It was not a stroke, then, but a more general power failure, the umpteenth to strike the city this year. And the voices he could hear were not those of the restless dead, seeping like moisture out of the ancient structures all around to claim the stricken Zen as their own, but simply the indignant residents of the neighbourhood who had been cooking or watching television or reading when the lights went out.

By the time he realized this, the darkness was already punctuated by glints and glimmers. In a basement workshop, a furniture restorer appeared, crouched over the candle he had just lit, one hand cupped around the infant flame. The vaulted portico of a renaissance palace was illumined by a bow-legged figure clutching an oil-lamp which cast grotesque shadow images across the white-washed walls and ceiling. From a window above Zen’s head a torch beam shone down, slicing through the darkness like a blade.

‘Mario?’ queried a woman’s voice.

‘I’m not Mario,’ Zen called back.

‘So much the better for you!’

Like a vessel navigating an unfamiliar coast by night, Zen made his way from one light to another, trying to reconstruct his mental chart of the district. Reaching the corner, he got out his cigarette lighter. Its feeble flame revealed the presence of a stone tablet mounted on the wall high above, but not the name of the street incised in it. Zen made his way along the houses, pausing every so often to hold his lighter up to the numbers. The flame eventually wilted, its fuel used up, but by its dying flickers he read a name off the list printed next to the button of an entry-phone. He pushed one of the buttons, but there was no response, the power being dead. The next moment his lighter went out, and his attempts to relight it produced only a display of sparks.

He got out his key-holder and felt the differing shapes and position of the keys. When he had identified the one he was looking for, he reached out both hands and palpated the surface of the door like a blind man until he discovered the keyhole.