His nephew has an inch-deep ravine in his neck; the rope caught hold of some hair at the back and imbedded it into that ravine that can only be caused by a long-drop hanging, and the old, retired detective is worried about a dog.

Starved of sleep, the old man spent most of the night cleaning his flat and watching reheated stories on the twenty-four-hour news channel.

He lit a candle. Not for the safe passage of his nephew’s soul, but for the smell in the living room. An attempt to burn away month-old curry and stale alcohol. The small amount of beer left in the bottom of some of the cans has leaked out of one of the bags onto the carpet that saw its first vacuum in weeks.

You’d think he was decluttering to clear his mind, ready for an investigation of his own, but you’d be wrong. It’s for the dog.

The upright cushion on his favourite seat is a different colour to the rest of the sofa, where his back sweats so much. He sits in it, watching that expert pontificate about nine people of whom he has no personal knowledge. And the news anchor thanks him, like he’s performed some kind of public service.

He forces his weight forwards and stands up. He hits the television button with the fleshy part of his fist to turn it off and goes into the kitchen. The drawer beneath the one where he keeps his cutlery is filled with tea towels and plastic bags and broken tools and lighters. But, at the back is an unused lunch box containing keys. Spares for the flat, his garage, his bike lock, and the set he had cut after Young Levant last worried him with his mood changes and nihilistic telephone chatter and that three-day disappearance.

Old Levant can’t stand the idea of that Alsatian been hungry and alone.

The old man walks down the stairs, two full bags of rubbish in each hand – he’s old but he’s still strong – and he throws them into a storage cupboard at the bottom, ready to put out on Wednesday night. Then he takes the bus to the ground-floor flat his dead nephew recently cleaned.

Ergo barks excitedly as the key turns in the lock. Like he’s hoping his master didn’t go through with it.

‘Hello, boy,’ says the old man, disappointing the dog, confirming that he has been left alone.

He kneels down, strokes the thing, unhooks it from the radiator and fills a bowl with dried food. Ergo eats. He obliges. He knows the dead boy’s uncle well enough not to feel threatened.

With the dog pacified, Old Levant picks up the telephone – he can get it cut off tomorrow – and calls the police to inform them that he knows the identity of the Man in the Light.