‘It needs to be something public and we’ll let the media get hold of it organically, keep it as credible as possible. Martello Court would be a good location. It’s the highest residential building in Edinburgh: twenty-three floors, two hundred and ten feet high. We stage it as a suicide threat in progress, drag it out, put cameras in place and wait to see who turns up. We’ve already got a lot of social media from the Stephen Berry attempted suicide. Maybe we’ll find an overlap, or the same interested professionals.’

‘We’d need a volunteer and they’d have to be willing to be monitored to protect their safety until we had a definite suspect in play. It would be a substantial intrusion involving possible danger.’ Ava looked around the room for raised hands.

‘I wouldn’t have suggested it if I weren’t willing to volunteer myself,’ Janet Monroe said quickly. ‘It makes sense. I’m the newest member of the team. I’ve never been involved in any police media work, plus I’ve been on the Jenson–Western investigation until now, so I haven’t been out to any crime scenes or spoken to any witnesses. I can talk about having a young baby and pretend I’m a single mother, so all sorts of potential for assuming I’m under pressure, compounded by being in a racial minority in Scotland, like Osaki Shozo. Gives me loads to say to whoever comes to my aid.’

Ava sighed. Janet Monroe was undoubtedly intellectually equipped to pull it off, but there was something unsettling about using a mother with a baby still not old enough to walk as bait.

‘Don’t even think about it,’ Monroe said directly.

‘What?’ Ava asked.

‘If I were male, would you have a problem with me volunteering?’

‘I need more time to think about it,’ Ava deflected. ‘It might be better to use an undercover specialist from a different area.’

‘You’ll have to brief them and get them up to date. I know what I’m looking for. I’ve read the file on every victim and I’m more than aware of the risks. My partner’ll take our baby out of the flat. He has family in Edinburgh. Let me do this,’ Monroe insisted.

Ava looked at her. Monroe could handle herself and Ava knew it. She was a good officer with great instincts.

‘All right. Tripp, Monroe, my office in ten minutes. We’ll need to complete risk assessments and set up surveillance. And I’ll need the superintendent to greenlight it. Confidential liaison with fire and paramedic units so they’re on standby. Armed police to confirm they can be stationed outside your property on a rotating shift basis. Let’s move.’

Pax Graham caught her as she was striding towards her office.