Levy did not reply. Instead she walked to the far side of the room and picked up a chair that sat in the corner. Placing it beside the corpse’s dangling legs, she stepped up. Levy was not a tall woman – little more than five foot five – but then Phillip Longman had not been a tall man. The seat of the chair was level with his crucified feet.

‘Pass me a glove.’

Levy did not look down as she spoke, or as she took the glove from Hale’s hand. Pulling the latex onto her fingers, she carefully opened Longman’s mouth. His castrated testicles had already been removed from inside, leaving a cavity with no teeth and no tongue. A blackened mess.

Levy leaned forward, putting her nose as close as she could without risking contamination of the evidence, and took a deep breath.

‘What is it?’ Hale was intrigued. ‘What can you smell?’

‘Bleach.’ Levy carefully closed the mouth and climbed down from the chair. ‘They filled his mouth with it, too.’

‘After he was dead? Why? What’s the point?’

Levy did not answer immediately. Instead she looked around and caught the eye of PC David Wright, who stood a little more upright under the DCI’s gaze.

‘Has a bleach bottle been removed from this room?’ she asked.

‘No, ma’am. Everything’s exactly as we found it. Other than any investigation of the body, obviously.’

‘What about downstairs? Or in the bathrooms? Have any bleach bottles been taken from any of them?’

‘I’ve no idea, ma’am.’

‘The body was discovered by the housekeeper, right?’

‘It was.’

‘Then go ask her. Take her to the rooms. We need to know.’

PC Wright left the room without another word.

Hale looked bemused.

‘What does a missing bleach bottle matter?’

‘It matters because it kills DNA, Steve.’ Levy had encountered the theory before. She had never seen it used. ‘The bleach wasn’t thrown over him to torture him. It was done to destroy evidence. That’s why the whole body’s drenched in the stuff. Whoever did this got down and dirty. Maybe that was the point. The thrill. But they also don’t want to get caught. They know what they’re doing, Steve. We won’t find anything on the body. And judging by the smell, the only DNA we’ll find in this whole bloody room is in that pile of sick by the door.’

Hale turned to look in the direction of the vomit. He then looked back at Levy.

‘But I don’t get why it matters if the bleach was taken? They won’t have left an empty bottle with fingerprints on it. Not if they’re that careful.’

‘It matters,’ Levy explained, ‘because if it was taken from here then it was a brainwave. An impulse. But if the killer brought the bleach with him, well, then we’re dealing with a professional. Someone who knew exactly what they were coming here to do. And how to cover their tracks. Important we know that, don’t you think?’