Kirby stared at him. ‘Say what?’

‘If the design was hijacked as you say, then why didn’t they paint out the seal of Wenkaura on the back panel? Why leave the insignia of a traitor on display for posterity?’

Kirby swallowed, thinking fast, eyes bulging.

‘It doesn’t make sense,’ Ben said. ‘They just wouldn’t have done that. Think about it. You’re a historian. When the Moors took Jerusalem from the Christians, did they leave a single cross standing? No, they hacked them all down and replaced them with their own crescent moon. And vice versa, when the crusaders came back to reclaim the city. That’s how it works. It’s the nature of war. The old order swept away by the new. Winner takes all. No compromises. What would be the point?’

The voices down below were getting a little closer.

‘And Wenkaura would never have made such a compromise either,’ Ben went on. ‘He was as much at war with the new order as they were with the old religion he represented. It would be a sacrilege to him to have his seal on this piece of Atenist propaganda. It would be like finding Winston Churchill’s signature on a swastika banner.’

Kirby frowned. ‘So what are you saying?’

‘I’m saying there’s only one possible explanation for why we’re seeing Wenkaura’s seal on what looks for all the world like a trophy captured by the enemy. It’s because these symbols weren’t put there by the enemy. They were put there by Wenkaura himself Ben patted the leather seat. ‘He fooled them. He had his own throne recovered with Atenist symbols, to protect it from being destroyed by the Pharaoh’s agents. And there’s only one reason he would do that. To preserve whatever it is he left inside. It’s a trick. Another clue in itself, telling us that there’s something hidden here waiting to be revealed.’

Kirby’s face brightened. ‘Shit, you could be right. Again.’

‘Feel this leather,’ Ben said. ‘It’s soft. Feels like sheep nappa, but it’s thicker than cowhide. There must be half a dozen overlaid panels of it making up the seat. My guess is we’ll find something under here.’

Kirby let out a gasp when he saw the small penknife in Ben’s hand. ‘You can’t do that-’

‘Yes, I can, and I’m going to.’

‘But it’s priceless.’

‘I’ll pay for it when we find the treasure.’ Ben slashed the leather open and carefully peeled back the top layer, praying the layers weren’t stuck together.

Underneath were colourful images of Thoth and Isis, Bastet and Anubis.

‘The old gods,’ Kirby said. ‘Akhenaten definitely wouldn’t have approved of that.’

But Ben still couldn’t see anything that hinted at a clue. ‘Fuck it,’ he muttered. He slashed again. Under the painted layer was a piece of plain hide, only slightly cracked with age.

Nothing.

But then Ben noticed something sandwiched between that and the layer below. He could barely make it out, but it looked like the yellowed corner of a sheet of papyrus. ‘Look at this,’ he said, moving aside.

Kirby examined it excitedly. ‘We have to be really careful. It could just crumble away in our fingers.’

Slowly, delicately, they separated the layers of ancient leatherwork until the papyrus could be removed intact. Kirby slid it out and balanced it on his palms as though it could disintegrate into dust at any moment.

The two of them peered down at the old document. In the upper corner was the seal of Wenkaura that was becoming familiar to Ben. Below that was a faded block of delicately painted hieroglyphs that meant nothing to him. But the design in the centre of the yellowed, time-frayed page was unmistakable.

‘It’s a map,’ Kirby breathed. ‘This is it, then. We’ve found it.’

Time was ticking away dangerously. Ben snatched out his phone and took a snap of the papyrus up close. The voices below were getting louder.

‘This is just incredible,’ Kirby muttered, already deciphering the glyphs, his head bent over in concentration.

‘No time to hang around.’ Ben grabbed the papyrus map from Kirby and started folding it up to put in his pocket.

‘Don’t-’

But it was too late. The ancient document was already breaking up into dusty shards that fell through Ben’s fingers.

‘That was probably the oldest map in the history of Egypt, and you’ve just destroyed it. Nice work.’

‘The historians don’t know about it, do they?’

‘And now they never will.’

‘So what they don’t know won’t hurt them.’ Ben grabbed Kirby’s arm and yanked him to his feet. ‘Enough talk. Let’s go.’

‘Where? Security’s all over the building.’

Ben walked over to the window, yanked aside the heavy drapes and threw it open. French doors led out onto a little stone balcony. He stepped out onto it and looked down. ‘This way.’

‘No way I’m climbing down there,’ Kirby protested. ‘We’re three storeys up.’

‘Then we’ll have to go out the front door, same way we came in.’

‘We’ll be caught.’

Ben walked away from the window and up to Kirby. ‘Hold still.’

The historian looked around him in panic. ‘What now?’

‘Just don’t move. I don’t want to hurt you more than I have to.’

Kirby opened his mouth to reply when Ben socked him on the chin. It was a good punch, not hard enough to cause any real damage, but it knocked Kirby out cold. Ben caught him before he could slump to the floor, flipped him up with a grunt of effort and carried him over his shoulder to the door. He threw a last look at Wenkaura’s throne and stepped out into the corridor.

The coast was clear-for now. Ben carried Kirby’s unconscious body down the winding backstairs. He used the historian’s feet to shove open a fire door, then made his way down a corridor with offices on both sides and a door that said ‘Gentlemen’.

Up ahead the corridor curved around to the left, and Ben could hear rapid footsteps coming his way. He eased Kirby’s weight down off his shoulder and laid him down on the floor. Kicked open the toilet door, dragged him half inside and let him sprawl limply on the tiles. He quickly arranged Kirby’s arms and legs to make it look as if he’d collapsed. Then he kneeled beside him, pressed his hands flat on the historian’s chest and started pumping hard, up and down.

The footsteps in the corridor reached the door. Ben looked up. ‘In here!’ he yelled. ‘Security!’

Two Embassy security guards in black suits appeared in the doorway. They both had radio earpieces and were holding pistols. ‘What happened here?’ one of them asked. ‘The building’s been evacuated.’

‘I’m a doctor,’ Ben said. ‘This man’s had a heart attack. Get an ambulance, right now.’

Less than fifteen minutes later, Kirby was waking up in the back of the lurching, swaying ambulance as it sped towards the hospital, siren wailing. His eyes fluttered open. ‘Where the hell am I? What happened?’

‘Be quiet, you’re dying,’ Ben said.

Kirby winced, put his hand to his face. ‘You almost broke my jaw. Ouch. Jesus.’

‘I needed you to be believable in your role. And you were.’

Kirby sat up. ‘Where are the paramedics?’

‘You’re in luck. They don’t seem to have them in Egypt.’

‘You bastard. You stitched me up. They’ll put those electric shock pads on me, won’t they?’

Ben could feel the ambulance braking to a halt. Through the window he could see they were still somewhere in the city, and caught up in a gridlock of traffic. Horns were honking as the jam thickened up ahead.

‘This is our stop.’ He grabbed Kirby’s wrist and hauled him off the bed before he could say anything. Opening the back doors, they stepped out into a sea of traffic and lights. Motorists stared as the two guys in tuxedos walked calmly away from the ambulance, headed for the pavement and mingled with the crowds.