‘Perhaps.’ Holm moved his attention from the screen to the quayside. A huge container ship was easing away from the dock. The water frothed and boiled as the bow thrusters and the rear screw worked the vessel sideways. A series of Chinese characters were painted at the bow and Holm wondered if the ship’s destination was the Far East. All of a sudden he had a weird notion it might be rather nice to be on the proverbial slow boat. Weeks at sea, the route mapped out, no decisions to make.

Cornish returned a few minutes later with a tray laden with cups of coffee and a plate of sausage rolls. As she and Javed tucked in, Holm went over to the window.

‘You’re right, Billie,’ he said. To hell with it, he couldn’t bring himself to deceive her any longer. ‘We’re talking terrorists, but it is vitally important the information stays secret.’

‘Christ.’ Crumbs fell from Cornish’s lips and she reached for a paper napkin. ‘How many?’

‘Two, we think. One of them at least was part of the group that carried out the Tunisian attack. The one I fucked up on.’

‘But JTAC and the security services are all over this, right?’ Cornish put down her plate and joined Holm at the window. She gestured across the estuary towards the town of Harwich on the opposite bank. ‘I mean, you’ve got agents out there ready to track these people. To take them down at the appropriate time.’

Holm continued to stare out of the window. He didn’t speak. The Chinese boat had left the port and was steaming towards the open sea.

‘Stephen, it’s just you? Can you tell me why?’

‘Walls and ears, Billie. That’s why. We’ll be going to my boss as soon as we know what we’ve got. Until then I’d be grateful if you’d keep to our original story about the Nazis.’ Holm turned and smiled. ‘And yes, I’d be grateful for your help too.’

Cornish smiled back but before she could speak Javed was on his feet, binoculars raised to his eyes.

‘She’s here,’ he said. A small container ship was passing to starboard of the Chinese vessel and a pilot boat was waiting to guide her to a berth. ‘The Excelsior.’

Trap or not, they headed east, skirted London and took the motorway to Cambridge. A succession of smaller roads followed until they eventually coasted along a country lane that ended at a small copse overlooking RAF Wittering.