Tennant was sweating from the exertion of the walk from Downing Street by the time he signed in at the entrance of the suite and locked his phone in a pigeonhole. He stepped into the clear plastic security pod which scanned him before letting him into the lobby. His staff officer and two sergeants had arrived twenty minutes earlier and were monitoring a computer screen in a small bunker off the lobby.

‘Any more on the manhunt?’ said Tennant.

‘CCTV search has yielded nothing so far,’ said the staff officer. ‘Social media contacts still being chased down, as is his internet and phone data. We’ve had angry statements from the usual suspects on the left and there’s a call for a peace protest in London for Saturday, organised by anti-fascist groups and which has already been supported by the leader of the opposition on Twitter.’

‘It didn’t take her long to jump on the bandwagon,’ muttered Tennant.

#

In the COBRA meeting room, Tennant looked for his name card and glanced at the single-sided agenda on the table as he took his seat. His was one of the few spaces with a computer screen and keyboard, which allowed him to communicate with his officers in their bunker off the lobby. He sat, suddenly conscious of a white stain on his tie. Where the hell had that come from? He attempted to scrape off the mark with a bitten thumbnail.

Seconds before 3pm, the Prime Minister took his place at the head of the table, facing the TV screens. ‘Let’s keep this brief, please. First over to JTAC.’

JTAC, the Joint Terrorism Analysis Centre, was an arm’s-length body that worked closely with MI5’s counter terrorism branch to assess the threat to the UK. The director of JTAC, a quietly spoken dark-haired man who resembled a librarian, cleared his throat. ‘Thank you, Prime Minister. In light of the nature of today’s attack, we are leaving the threat level at severe.’ Tennant fought to control his frustration. That was ridiculous. He had briefed JTAC half an hour earlier that there was a real threat of a follow-up attack.

The director continued: ‘This decision is on the basis that today’s attack involved only one known individual, although of course he may have had an accomplice, no sophisticated weaponry or explosives, and the wider intel picture that the National Resistance Force is unlikely to have the resources or capability of organising sophisticated, or multiple, attacks.’

Tennant felt himself reddening. He could not challenge the director in COBRA, but equally, he could not hold his tongue.

‘Prime Minister, I do think there are some facts beginning to point to this being part of a more sophisticated plan that leads me to be concerned about further attacks,’ he said. ‘The context of the rise of the extreme right wing, which I’ve expressed concerns about on many occasions, also needs to be considered carefully. But I accept these are fine judgements and JTAC has a tricky job with a limited intelligence picture.’ The director of JTAC shot a glance at him. He hadn’t meant to use the phrase limited intelligence, but too late now.