Whiting’s mouth twisted, as if she were already testing the limits of clearance. ‘Their history goes back to the early noughties, when Mardell bought in. For over a decade, they existed as typically benign sun worshippers, rarely drawing interest from the law, except when they trespassed on private, supposedly sacred land. But three years ago, there was a change in their behaviour. They started showing up at gatherings organized by other groups, arriving covertly in small pockets before starting unprovoked fights, allegedly to break up the events. These interventions became increasingly violent, involving several hospitalizations by the middle of last year. Looking at the pattern in hindsight, you can see things building, potentially towards the nail bomb incident, although guerilla tactics, plus their victims’ reluctance to involve the authorities, mean this is all conjecture. None of the group, including Mardell, has ever been picked up for any of it.’

‘Then how do you know it’s them?’

‘We have our sources.’ The superintendent half-smiled. ‘Not close enough to implicate the ringleaders, but with ears much closer to the ground than our own.’

Hawkins realized that particular thread was going no further. ‘Then why the change in their tactics?’

Whiting linked his hands on the desk. ‘We think the community elected new leadership at some point in 2012, a new incumbent who began instigating this more extreme approach.’ His answers were becoming more clipped.

‘Do we know who?’

‘We have our suspicions. Which, unfortunately, I’m not at liberty to discuss.’ Whiting studied her. ‘Why was he arrested?’

Now it was Hawkins’ turn to choose how much to reveal. She decided that being honest with someone as clearly professional as Whiting held little risk. ‘We’re investigating a string of murders, all young men, bodies left in abandoned houses. All the victims were involved with various spiritualist groups, and at the last murder scene we found this symbol.’ She showed him the photo on her phone.

Whiting leaned closer. ‘I don’t recognize it. What does it mean?’

She explained.

The superintendent listened intently, then commented, ‘Given your explanation, I wouldn’t rule out Millennial Dawn’s involvement, but it would signal a change from their previous, more open attacks. How is Mardell involved?’

Hawkins told him about their captive’s appearance outside Joseph White’s office, her attempt to approach him; the chase along Oxford Street. She turned her face to show off the bruise developing on her jawline. ‘He wasn’t keen to chat.’

‘I see. What do you think is going on?’