For once Jo did what she was told and in one movement swung herself over the wall and onto the pavement on the other side.

The two uniformed officers started to pull the battering ram back into position. But before they’d had a chance to drive it forward, Mark Stone had taken a running jump and with his arm covering his face had launched himself clean through the bay window, glass and all. Within seconds he had the front door open.

The two constables laid the battering ram down and followed him into the house.

Jo could hear Stone talking to them. ‘He’s locked this door. He’s in there. She seems to be on the other side of another door. He’s hammering at it with something. Where’s that battering ram?’

Shit! Clare was in there with Fuller. And he had her trapped. There had to be another way in. Jo glanced to her right. About four doors away was a side passage leading down the side of one of the houses. That had to go somewhere, didn’t it?

She ran like her life depended on it, following the passageway down until it hit a T-junction. Then she headed left. How many houses down? It was four. She was sure it was four. One, two, three, four. Looking up she could see the same peeling red paintwork. This was it. The wood of the back gate had long since rotted. She gave it one swift kick and the little that still remained disintegrated. As it did so it revealed a sea of chest-high stinging nettles. Above them Jo could see the back of the house. To the right was what looked like it must be the kitchen window. Someone had installed steel security bars across it. Through the grime-stained glass she could see what appeared to be a table that had been upended and jammed up against a door.

To the left of the kitchen window was a brick-built extension that must once have been an outhouse of some kind. On its gable end was another window, this one double-glazed and with frosted glass. It must be the bathroom. The window was split into two parts. The bottom two thirds was a single solid pane. But the top third looked as if it opened outwards.

She cursed the summer sunshine she’d been so glad of that morning. Her denim jacket was still sitting where she’d abandoned it in the site office. Lifting both hands in the air, she waded into the ocean of green. The thin cotton of her T-shirt did little to prevent the hundreds of tiny hypodermic needles from finding their mark. Gritting her teeth, she plunged forward. After the first five or ten seconds she almost ceased to feel the individual stings. The whole of her upper body felt as if it had been rubbed with red hot chilli peppers.