There was a noise from beside her. A text message. She was startled to see it was from Costain. He was wondering if she ‘had five minutes’.

What? At this time in the morning? He’d never texted her before. He was probably drunk. Or was this meaningful? Was this the start of the sort of activity on his part that she’d told herself to watch out for? Whatever. She put the phone back down without replying.

Costain was the one from whom she especially needed to keep this work secret.

*   *   *

Quill was once again hauled awake by the sound of his phone. His dreams had been full of something reaching towards him, reaching into him. But he couldn’t remember it now. Jessica, unwoken by the sound of the phone, was lying across his head.

‘Would you please answer that,’ said Sarah, ‘and tell them to –’ she looked at her daughter and gritted her teeth – ‘go away?’

Quill saw that the call was again from Ross, and said so.

‘Getting over her now,’ said Sarah.

He picked it up. After listening for a few moments, he quickly got out of bed and started getting dressed.

‘What?’ moaned Sarah.

‘Another one. It’s police.’

*   *   *

The slightly portly middle-aged man lay across the sofa. He was still dressed in a blue towelling robe, the now-familiar silver fluid splattered across him and all over the room. The robe was open, and so was he. A livid red trail led from what remained of his abdomen, across the polished wooden floor, and finished in an explosion of blood against the far wall, next to a Jack Vettriano. The expression on the victim’s face was an almost comical extreme of horror and incredulity. His eyes were open, glassy.

Quill’s team stood in the doorway, feeling – if Quill himself was anything to go by – like anything but an elite unit at this hour of the morning. Forensics had just finished with the crime scene and were packing up. Uniforms were filling just about every available inch of the building.

What they were staring at was enormous. Bigger, even, than the death of a cabinet minister.

‘Sir Geoffrey Staunce, KCBE, commissioner of the Metropolitan Police,’ said Ross, keeping her voice low as a uniform made her way past.

‘They got him,’ said Quill. ‘That’s what the papers are going to say tomorrow. With a strike looming, the protestors killed London’s most senior copper at his home in Piccadilly.’

‘There were indeed Toffs in the area last night, making a nuisance of themselves,’ said Ross, looking up from the report she’d been given on entering. ‘For this sort of address that’s pretty incredible.’

‘The connection is also the locked room and the MO,’ said Quill.

‘Plus, from our point of view, the silver goo,’ added Sefton.

‘And,’ said Costain, ‘the wife is talking about an invisible assailant.’