There was a short, weighty silence before the national security adviser responded. ‘We think,’ he said, ‘the answer may lie in Lithuania. GCHQ have traced a connection to a suspect factory there.’

‘Well, what are we waiting for?’ The PM looked from one to the other, eyebrows raised. ‘Let’s get someone over there ASAP. I’ll get Cheryl to clear my diary so I can chair the COBRA tomorrow morning.’

27

Kirtimai Industrial District, Vilnius, Lithuania

Thursday, 10 March, 0835hrs GMT, 1135hrs local

GREY, UTILITARIAN AND unspeakably grim. Luke’s first impressions of the industrial suburbs of Vilnius were far from favourable. Could this really be the picturesque Baltic capital so beloved of British stag weekends, the place he’d heard so much about? He shrugged. He was here to do a job. And this was definitely a last-minute rushed tasking, with minimal time for prep. He and Jenny Li had still been inside the Doughnut at Cheltenham yesterday when the order came through from Vauxhall. They were both to head back to London immediately, ready to catch the early-morning LOT Airlines flight from City Airport direct to Vilnius. Their cover stories were already being worked up by the security team.

‘You’ll be going in under official cover,’ Angela had told him, on the phone from Vauxhall, as they made their way to Cheltenham railway station. ‘You work for the OPCW. That’s the Organisation for the Prohibition of Chemical Weapons. They’re based in The Hague.’

‘I know,’ Luke said patiently. ‘I worked on the Novichok case in 2018, remember?’

‘Yes, of course you did,’ she added, in a conciliatory tone. ‘Anyway, all of that, plus your biogs and your social-media back stories, will be coming through on your phones in the next few hours.’

‘ID? Passports?’

‘Already being prepped,’ Angela had replied. ‘When you get to City Airport go straight to desk thirty-four and someone from Security Branch will be there at check-in and hand them to you in a white A5 envelope. She’ll be dressed in a dark blue jacket with a red, white and blue scarf. It’s the LOT Airlines uniform.’

‘What, no code words?’ Luke had replied. ‘No “geese flying south in winter” exchange?’

‘Don’t be facetious, Luke. This is deadly serious.’ Her voice sounded stern now and he immediately regretted trying to make light of the situation. ‘This tasking,’ she said, ‘has come direct from Number Ten.’

Luke and Jenny had travelled back to London in almost total silence, with him reading up everything he needed to on his mythical role as a technical inspector at the OPCW, the chemical-weapons watchdog, while Jenny was absorbed in the stream of data coming into her laptop, occasionally muttering cryptically, ‘No, no, this is not good.’ And now here they were, less than twenty-four hours later, on their way to a chemical factory in an obscure corner of Eastern Europe.