Kamal stopped firing, and the M60 hung loose in his hands. He flashed a dangerous look at Youssef. ‘Don’t ever question me again, old friend.’

‘I’m sorry.’

Kamal propped the gun against the side of the well. ‘I never liked him anyway.’ Grabbing the Maglite from Youssef’s hand, he shone it down the hole and gazed impassively at the broken, mutilated corpse at the bottom, half covered in loose clay and dirt.

‘We should move on,’ Youssef said, averting his eyes.

But something else had caught Kamal’s attention, and he swept the torch beam upwards. The raking gunfire had collapsed a section of the shaft wall about halfway up.

And there was something really strange down there.

It wasn’t natural rock he could see behind the clay. It was smooth, worked stone, and he could make out odd markings on its surface. Rows and columns of them, man-made and ancient-looking. He narrowed his eyes. What the hell?

‘What are you looking at?’ Youssef said.

Kamal didn’t reply, just pocketed the torch and tugged on the rope. It was loose, severed by the bullets and he pulled it up. It was spattered with Hani’s blood, but Kamal didn’t care about that. He looped it around his own waist. ‘Lower me down,’ he commanded.

With his legs and back braced against the shaft wall he held the torch with his left hand and used his combat knife to hack away at more of the clay, bits raining down to bury Hani’s corpse below.

Digging furiously, Kamal could see this was no ordinary stone slab. It had corners that extended deep into the sandy earth. The more he dug, the more he realised that it was a chamber of some kind, buried far underground. And it had been there a very long time.

In the torchlight he studied the strange markings in the rock, and realised what he was seeing. These were hieroglyphs, and they had to be thousands of years old. They meant nothing to him, but he was smart enough to know there was something behind here. Something inside.

But what? He had to know.

He yelled for someone to toss down his bag and moments later the small military knapsack was tumbling down the hole. He caught it, slung the strap around his neck and reached inside for one of his plastic explosive shape charges.

As he emerged from the hole, the others were firing inquisitive looks at him. ‘What is it?’ Youssef asked, frowning. Kamal was already reaching for the remote detonator, gesturing at them to follow him.

Behind the cover of the trucks, he activated the charge.

Fire and smoke blasted from the hole. Flying debris showered down and rattled off the vehicles as the men shielded their faces. Smoke drifted across the sand.

Before the dust had even settled, Kamal was on his feet and striding back towards the shattered well. He grabbed the rope and slithered over the edge, his torchbeam cutting through the vortex of smoke and dust.

The blast had crumbled away a large part of the shaft wall. Hani was now completely buried under a ton of dirt. But Kamal had forgotten all about the dead man.

His instincts had been right. There was some kind of hollow chamber here. His heart beat fast as the torchbeam settled on the long, ragged split in the stonework. The shape charge would have cut a neat square in a modern block wall, but this was solid stone and two-foot thick. Kamal used the shaft of the torch to knock away loose pieces of masonry, and stuck his hand through the hole. Cool air on his fingers.

He pulled out his hand, poked the head of the torch through the split and peered in after the beam.

And his breath left him when he saw what was inside.

Chapter Two

Near Valognes, Normandy, France

Seven months later

Except for the light rain that pattered off the roof of the little house in the woods, everything was still.

At the edge of the clearing, a twig snapped. A startled rabbit looked to the source of the sound and darted for cover.

The six men who emerged from the bushes were all wearing green camo fatigues. They kept their heads low as they stalked out from the foliage, eyes darting cautiously this way and that, moving towards the house with their weapons cocked and ready.

They knew the children were inside, and they also knew that it was going to be difficult to get in there.

The team leader was the first to reach the old peeling door. It was locked, but he’d expected that. He backed off two steps and covered the entrance with his pistol while the guy to his left flipped the safety off his cut-down Remington shotgun and blasted the lock apart. The deafening gunshot was absorbed by the electronic earpieces the men were all wearing. The shattered door crashed inwards.

The team leader went through first. As the entry man, he’d been taught that he could expect to take a hit, or at least get shot at, as he went in. He’d also been taught that, in the heat of the surprise assault, the kidnappers’ fire would be rushed and inaccurate. He trusted his body armour to take the hits while he returned fire and took the shooters down.

But there was nothing. The hallway was empty, apart from the ragged splinters of door that the shotgun blast had blown across the floor. The team split into pairs, covering each other at every turn through the bare corridors. They moved slickly, weapons poised.

A door suddenly crashed open to the left and the team leader whipped around to see a man lumber out of the doorway. There was a stubby shotgun in his hands, the muzzle slung low at his hip. He worked the slide with a sharp snick-snack.

The team leader reacted instantly. He brought his Glock 9mm around to bear, relying on instinct and muscle memory more than a conscious aim. He fired twice. The kidnapper fell back, dropping the shotgun and clutching his chest.

The team moved on. At the end of the corridor was another door. The team leader booted it in as the others covered him. He burst into the room and the first thing his eyes locked onto was the old armchair in one corner with the stuffing hanging out of it. He glanced around him, adrenaline screaming through his veins.

In the other corner of the half-lit room was a dingy mattress, and on it were the two children.

The little boy and girl were strapped together, back to back. There were hoods over their heads, the girl’s long blonde hair sticking out from under the rough sacking cloth. Their clothes were torn and grimy.

The six men quickly covered the room with their weapons. There was no sign of the rest of the kidnappers. The silence in the place was total. Just the wind in the naked branches outside, and the cawing of a crow in the distance.

The team leader strode up to the children, holstering his weapon.

He was just three steps away from them when he saw it. By the time his brain had registered the device attached to the girl, it was too late.

The flash was blinding. The team members instinctively covered their faces, mouths dropping open in shock.

The incendiary device was small but potent. The children burst alight, their bodies twisting and tumbling, the flames curling around them, melting their clothes. Beneath the flaming hoods, their hair burned and shrivelled. The sackcloth dropped away to show the white, staring eyes in the blackening faces.

The room was filled with smoke and the acrid stench of melting plastic as the burning mannequins collapsed onto the mattress. Fire pooled all around them.

A door flew open, and a blond-haired man walked into the room. He was tall, just under six feet, dressed in black combat trousers and a black T-shirt with the word ‘INSTRUCTOR’ spelt out in white lettering across his chest.

His name was Ben Hope. He’d been watching the trainee hostage rescue team on a monitor as they’d approached the purpose-built killing house he used for tactical exercises.