Zach vigorously shook his head but Lesley put her hand on his back and eased him forward until he could stick his head round the corner.

‘Would you be kind enough to tell them we come in peace?’ said Nightingale.

‘Do you think anyone has ever fallen for that one?’ asked Zach.

‘I don’t wish them to fall for anything, Mr Palmer,’ said Nightingale. ‘We need to establish an arrangement, or I fear things could become difficult.’

‘What makes you think they’ll be interested?’ asked Zach.

‘Had they wanted to, they could have shot us down already,’ said Nightingale.

The CO19 officer on the left cleared his throat. ‘We generally seek to de-escalate these confrontations as soon as possible, sir,’ he said. ‘The longer they go on, the greater the likelihood of a sub-optimal outcome.’ It was an impressive speech from a man who was obviously dying to retreat back the way he’d come.

‘Duly noted,’ said Nightingale.

‘For god’s sake Zach,’ I said. ‘Usually we can’t get you to shut up.’

Zach sighed and edged forward until he could look over Nightingale’s shoulder.

‘Yo!’ he called. ‘Is Ten-Tons around? I’ve got a man here wants to talk to him.’

He held our breath. I heard a voice, nothing more than a whisper floating out of the dark.

‘Did you hear that?’ asked Lesley.

Zach shushed her. ‘I’m trying to listen here,’ he said, and then called over Nightingale’s shoulder. ‘What was the last bit?’

Lesley rolled her eyes but stayed quiet – I still couldn’t make out any words.

‘He says that the Nightingale and the soldiers got to stay out, but they’ll talk to the half-caste.’ He looked at me. ‘That’s you, by the way.’

‘Why me?’ I asked.

‘I don’t know,’ said Zach. ‘Maybe they just don’t rate you very highly.’

‘You’re certainly not proceeding on your own,’ said Nightingale.

We were in total agreement on that.

Half-caste, I thought. I hadn’t heard that one in a while. Not since Mum fell out with Aunty Doris who, having grown up in Jamaica in the 1950s, regarded political correctness as something that happened to other people. If they were old-fashioned about that, I figured, they might be usefully old-fashioned in other ways.

‘Tell them we want to bring in a nurse,’ I said. ‘To make sure everyone is healthy.’

‘What are you thinking, Peter?’ asked Nightingale.

I turned back and beckoned to Agent Reynolds, who was at the back with Kumar, closer.

‘Are you tooled up?’ I asked.

She looked puzzled for a moment and then nodded.

Lesley poked me in the arm. ‘Not without me,’ she said.

‘Two nurses,’ I told Zach.

To preserve their night vision, we were keeping our torches pointed away from the CO19 Officers and Nightingale, but even half shadowed I could see he didn’t like the idea of sending women into danger.