She regarded him for a moment. ‘Don’t worry, I believe you. But there are still question marks over your group’s activities.’

‘People fear what they don’t understand. That doesn’t make us dangerous.’

‘Agreed. Except in this case, someone has killed five young men.’

‘Well, it wasn’t me.’

‘That’s what most murderers say. But we also know about Millennial Dawn’s intolerance of rival belief systems and your, how can I put this, disruptive activities at their gatherings. I should also mention that all five victims were involved with spiritualism to varying degrees.’ She sat back, crossing her arms. ‘According to our pathologists, the latest victim died between twenty-four and forty-eight hours ago, well before any of you were arrested at the old factory. Which is why my team is busy checking your gang’s accounts of their movements over the last few weeks. Yours included.’ She paused for effect.

Byford didn’t react.

She let the silence hang, her mind automatically switching to other tasks, making a mental note to check in with Chris and Frank, who had spent the morning painstakingly piecing together the otherwise apparently normal lives of Byford’s ritualistic chums.

Progress had been irritatingly slow, although at least the techs had made a breakthrough overnight, by unearthing a series of messages exchanged on social media by the original three victims. This in itself constituted a sizeable revelation, confirming not only that the men had known one another after all, but also lending weight to the theory that the three had been in some kind of trouble leading up to their murders. Hawkins had ensured that everyone involved was suitably commended; keen to rejuvenate flagging morale in the ranks. Her tactic seemed to have worked. Yet somehow, the discovery moved them no closer to understanding the motives, or the individual, behind these deaths.

‘I take it you’ve found nothing incriminating,’ Byford interrupted her thoughts. ‘Which, of course, you won’t.’

‘Don’t count us out just yet,’ she parried. ‘If anything’s amiss, I promise you’ll know straight away.’

‘How considerate.’ His smile was sarcastic. ‘I assume that concludes our business.’

‘Not quite.’ She produced an iPad, woke the screen and placed it on the table between them. ‘Do you know what this writing means?’

Byford stared at her for a few seconds before he leaned forwards and studied the photograph, of the writing on the wall at the flat in Camberwell. ‘Yes.’

Hawkins raised her eyebrows as he looked up. ‘Care to prove it?’

He hesitated. ‘Why would I assist you?’

‘Interesting response.’ Hawkins glanced at Aaron. ‘Some might say that not helping us makes it look like you have something to hide.’

‘Fair point.’ Byford read the scrawled letters again. ‘That’s Latin; it means something like he who is not welcome.’

‘Good.’ Hawkins swiped to the next image, a composite of the three large symbols from the adjoining walls. ‘How about these?’