And Cooper sat back, suddenly exhausted. He hadn’t realized how tense he’d been, the amount of nervous energy he’d been expending on willing the old man to speak, to stay aware for the amount of time he needed him to.

‘No, Mr Sutton,’ he said wearily. ‘It didn’t work.’

Raymond Sutton looked around the room, his eyes becoming vague as they met the light from the window. Tears glinted in his lashes and settled slowly on to his cheeks.

‘I want you to go away now,’ he said. ‘I want everyone to go away.’

Cooper caught himself shaking uncontrollably by the time he left the interview room. He couldn’t face the idea of crossing the car park from the custody suite and walking back up to the CID room to transcribe his notes, as if everything was perfectly normal. So he sat for a few minutes in his car instead.

He couldn’t conceal the fact that he’d found the interview with Raymond Sutton unbearably upsetting. But at least he knew why – and it wasn’t just some pathetic tendency to sympathize with the underdog, as Diane Fry would have suggested. Raymond Sutton’s rambling about his home being cursed had reminded him too strongly of his own mother at the height of her illness.

Specifically, it reminded him of one traumatic incident that had taken place just before the family had faced up to the fact that Isabel Cooper had deteriorated to the point where they could no longer keep her at home.

Above all, Cooper found that he was remembering the smell. It was as if it had seeped into his car silently and rapidly, like a lethal leak from his exhaust.

There had been a stink in the room worse than anything he had ever smelt on a farm. No cesspit, no slurry tank, no innards from a freshly gutted rabbit or pheasant had ever smelt as bad as the entirely human stench that filled the room. There was excrement daubed across the wallpaper, and on the bedclothes piled on the floor. A pool of urine was drying into a sticky pool on the carpet near to where similar puddles had been scrubbed clean with disinfectant, leaving pale patches like the remnants of some virulent skin disease. A chair lay on the rug with one leg missing. A curtain had been torn off its rail, and the pages of books and magazines were scattered like dead leaves on every surface. A pink slipper sat ludicrously in a wooden fruit bowl on the chest of drawers, and a thin trickle of blood ran across the top drawer, splitting into two forks across the wooden handle. The drawers and the wardrobe had been emptied of their contents, which were heaped at random on the bed.