When the bed was pulled away from the wall, one patch of paint was noticeably whiter than the rest.

‘That’s where she wrote her son’s name on the wall, but it’s gone now. Actually, there’s something else.’ Deborah stepped off the rug and flipped it over to reveal scratches on one of the floorboards. Sasha saw the initials JW scraped deep into the wood. ‘She must have used a set of keys, or a knife from the kitchen.’

Sasha crouched down and touched rough gouges at the end of the floorboard. She reached into her bag for her phone and turned on its torchlight, which was intensely bright in the gloom of the room. Dropping to her knees, she pointed the light at the floor.

Deborah leaned over. ‘What are you doing?’

‘There’s something down there.’ There was a sliver of a gap between the floorboard and the one beside it, and she glimpsed something red underneath. When she prodded the floorboard with her fingers, it rattled slightly, so she shuffled inelegantly on her knees to the end of the plank. ‘And there’s no nail here.’

Lolly lifted the rest of the rug to reveal the other end. ‘Or here,’ she said.

Sasha took the teaspoon from the mug and placed the handle end under the edge of the floorboard, using it as leverage to lift the wooden plank. It popped up easily.

‘Do you have any disposable gloves?’ she asked Lolly, who took a pair from her pocket.

Sasha snapped them on, reached under the floorboard, and lifted out a red notebook. She flicked through the stiff pages to find photos of Jeremy Weston. Jeremy as a baby, as a toddler, and as a little boy of six or seven years old. Every page contained photos of Jeremy Weston as a child.

‘Notice anything?’ said Sasha to Lolly. ‘They’re all of her son, they’re all of Jeremy, there’s not a single one of Lauren.’

She turned to the last pages. There were more photos, stuck in with glue, of Jeremy as an adult. They were all taken in the street, and he seemed oblivious to the camera. One of the shots was taken outside a shop: Jez was inside, half hidden by the reflection of the street in the glass, looking at something on one of the shelves. A caption written in a small, careful hand said, ‘Jeremy in shop!’

In another image he sat at a table outside a pub, laughing with friends or work colleagues, a pint halfway to his lips. The caption below it said, ‘Jeremy at pub!’ On the next page was a photo of Jez and Bethany walking hand in hand. The caption said, ‘Jeremy and Lady!’

‘Jeremy and Lady?’ asked Lolly. ‘Is Bethany posh?’