Holm shook his head and started to protest, but Javed was already moving back towards the hallway and heading for the front door.

Five minutes later Silva and Milligan were leaving the busy centre and strolling into Highgate Cemetery. Stillness. The peace of the dead. Milligan hadn’t spoken since they’d left the agency and now he led the way in silence, following a path that wound beneath huge trees, the light from above filtered to a soft lime by a canopy of leaves.

‘What’s going on, Neil?’ Silva said, trying to keep up. ‘What exactly was it my mother was working on?’

‘I told you, the trafficking story.’ Milligan hunched over and shuffled along. ‘She wanted to do a series, a piece on each country involved, she was interviewing the actors and—’

‘You said.’

‘I did?’ Milligan stopped walking and shook his head. His eyes were wide open but his pupils tiny. He glanced back the way they’d come. ‘Sorry. The past few weeks have been stressful. I’ve been under a lot of pressure.’

‘I’m sure you have. It must be difficult when one of your journalists is deliberately targeted because of a story she was working on.’

‘Yes, it…’ Milligan’s affirmative nodding stopped and changed to another shake of the head. He started to walk on. ‘No, Rebecca, not deliberately. Your mother was killed by terrorists in league with the people traffickers. Their target was the head of a charity providing help to refugees, and your mother and the other victims were bystanders unwittingly caught up in the attack.’

‘That’s bullshit. If it was really true then why couldn’t we have this conversation in your office? Why did somebody break into my mother’s house? Why was I followed by a mysterious car on the motorway and then later pushed into the weir?’

‘This isn’t a discussion I want to have, OK?’ Milligan increased his pace, striding away. Silva followed. ‘You’ve had a warning, you might say a lucky escape. Take my advice and move on.’

‘Move on? Are you fucking joking?’ Silva caught up with Milligan. She was angry at the way he was being so dismissive. ‘My mother was murdered and I’m beginning to suspect the facts aren’t as simple as the authorities are making out.’

‘Forget it, right? Forget whatever you think you know.’

‘It’s Hope, isn’t it? Karen Hope?’

Milligan stopped and spun round. He shot a hand out and grabbed Silva by the wrist. ‘For God’s sake don’t mention her name.’

‘Why ever not?’

‘Because I told you not to, OK?’

Silva paused and lowered her voice. ‘How has it come to this, Neil?’