The engine noise died down as the pilot pulled back on the throttles of the remaining two engines to idle and the nose of the plane went up. Shepherd almost lost his balance and Gannon reached over to steady him. The Nimrod shuddered as the pilot fought to keep it steady at the close-to-stalling airspeed. Shepherd looked through the open door at the black night sky, peppered with a million stars. Far below was a layer of thick cloud, from fifteen thousandfeet to six thousand, which meant gliding through nine thousand feet of close-to-freezing water vapour. That and the landing would be the most dangerous phases of the operation. It was easy to get disoriented in cloud and there was a risk of collision – dealing with tangled chutes in cloud at night was an interesting proposition that Shepherd was keen to avoid.

The amber light winked off and the green light went on. Gannon grinned at Shepherd, behind his mask, then jumped out of the exit door, thrusting out his arms and legs in a starfish pose. Shepherd took a deep breath and followed him. He gasped as the wind tore at him, pulling, twisting, pummelling. He fought to keep his arms and legs out as he fell through the slipstream. As soon as his descent stabilised he pulled in his arms and legs slightly, adopting the stable position, his back arched so that his centre of gravity shifted towards his stomach.

Gannon was to his right so Shepherd crabbed towards him, feeling the air pressure shift under his body. More of the troopers joined them and Gannon turned slowly, checking numbers until he was satisfied that everyone was in free fall.

They reached twenty-six thousand feet above sea level and the automatic opening devices kicked in. Shepherd felt a tug at his shoulders as his canopy deployed, then his arms snapped in and his legs went down as the chute filled with air and slowed his descent. He reached up for the toggles that controlled his direction and pulled the left one, heading after Gannon, then checked his jet-black canopy. It was fine, totally rectangular, no tangled lines. In the distance, the engines of the Nimrod were a dull roar.

Shepherd tilted his head down and looked at the chest-mounted liquid crystal display screen of his GPS system. It showed his position and, some forty miles to the south, a red dot that represented the tanker.

He looked over his shoulder. Behind him, he could see the rest of the troopers, their canopies unfurled. He did a quick count. So far so good.

The harness was biting into his groin and Shepherd kicked out with his legs, moving the webbing. He took a deep breath of oxygen and let it out slowly.

‘You okay, Alpha Two?’ Gannon’s voice crackled in Shepherd’s earpiece.

‘No problems,’ said Shepherd.

‘Just sit back and enjoy the ride,’ said Gannon.