The door to the lounge was shut tight, and Dorothy felt a prickle of apprehension as she put her hand on the handle. She walked into the lounge.

The gas fire was on full and the television was showing a children’s puppet programme. Her mind registered these facts. Her eyes, though, were on her friend.

Dorothy just stood and stared at the remains of Leonora Davidson.

Finally, after what seemed an eternity, she screamed - a high-pitched, animal scream that bounced around the tiny room, filling it with her fear and outrage.

As a parting shot, George had stuck the breadknife through Leonora’s left eye socket.

Her naked legs were sprawled in front of the fire, and had been gradually singed during the course of the night. Somewhere in the back of her mind Dorothy realised that that was the funny smell.

Burnt meat.

Caitlin and Kate were elated. The killer had once again changed tack. He had gone into someone’s home. That meant one thing: the victim knew him.

The door-to-door was trying to establish not only people’s whereabouts, but also whether or not they had seen anybody either in or near the block of flats.

Kate’s elation soon dissipated when she saw the woman’s body. What kind of man would do that to another human being?

‘There’s semen on the mouth, breasts, and in and around the vagina. I’d hazard a guess our man went on rather a spree last night. She’s been buggered, I’d lay money on that one.’ The pathologist shook his head.

Caitlin was staring at the woman as if committing her to memory. She still had the breadknife jutting from her eye, like a grotesque statue. At least someone had turned off the gas fire and opened the windows.

All around people were getting on with their jobs. Scenes of Crime were taking photographs. Taking fibres from the carpet and furniture. Picking up individual hairs. Taking samples of blood from the body, the chair and the carpet. Kate saw one pop the two coffee cups into plastic bags for fingerprinting and knew immediately that would get them nowhere. He always wore gloves. Always. He was as shrewd as they come.

Caitlin pulled his gaze from Leonora’s body and his eyes burned into Kate’s.

‘There’s got to be something this time. He’s not the Invisible Man, for God’s sake. Someone must have seen him.’

Kate wasn’t sure who he was trying to convince.

‘The two women who discovered the body are both in hospital. Shock.’

‘Well, I should think they are, Katie. Look at what they stumbled on. But this time we’ve got him. I just know it. I feel it.’

She hoped that Caitlin was right.

‘Are you coming with me to watch the post mortem?’

He nodded.

‘Yes. I’ll be there, Katie. I want to know everything. Something is going to lead us to that bastard. I just know it.’

DS Spencer came into the tiny room and stared at Leonora’s body. She was rapidly greying. He stared at her hard, like Caitlin before him.