Ava took the stairs slowly, keeping her gloved hands off the bannister to avoid smudging any prints, looking at the carpet as she went. Here and there were dark red drips, but the only violence seemed to have taken place downstairs. What cause did the killer have to go upstairs after the event? Surely he’d want to exit the house as quickly as possible. The gunshot could have been heard from quite a distance at night. He was also contaminating the scene more than was necessary, something he’d been careful not to do at the other crime scenes, if – and she accepted it was a big if – he was the same man who’d killed the other victims.

At the top of the stairs, she paused. Either the killer had been looking for something, although robbery was clearly not the primary motive given the feathers, or he’d been spooked. It was an old house and entirely possible that squeaking floorboards had got the better of his imagination, but then there’d been a burned apple pie that the forensics team had put on the kitchen table. A large one. Too large for one man to eat alone. The farmer hadn’t been skinny but he was far from obese. Certainly not a whole-pie-in-one-evening kind of figure.

Ava took the rooms one by one, clockwise from the top of the stairs, checking each cupboard, looking for signs of inhabitants. In the main bedroom she noticed the flowery bedspread and something else in a bedside cabinet. Tucked in the drawer along with a fly-fishing magazine and a torch was a half-used pack of condoms. Someone had been here, regularly enough for Jon Moffat to have planned for sexual encounters. She squashed the memory of when she’d last been looking for the same items, and the flash of pain that took her unawares with it, and got on with the job in hand. Nothing like a brutal murder to help get priorities straight, she thought.

In the final room, Ava opened the built-in wardrobe, noting the bloody handprint inside the door and calling down to the Scenes of Crime officers to come and photograph it. Stepping inside and to the very back, she heard a hollow thud beneath her foot.

‘Tripp,’ she called, kicking the bedding out of the way. ‘Guest bedroom, now!’

She banged hard on the floor. In spite of the carpeting, the hollow sound of it was obvious compared to the solidity of the rest of the area. Running her finger around the edge of the carpet, she hit a loop of electrical wire. Clever. Hard to notice. Would have looked like a stray lead to anyone not looking for it.