The khan leaned heavily back in his chair and regarded Erlan with his full attention. ‘I may be an old man now, but my memory is not so dim I cannot think back two years. The man with whom I made my alliance was not your master.’ His vast belly shook, but whether with mirth or anger, Erlan couldn’t be sure. ‘The basíleus – as you call him – is a usurper. He stole his throne from my ally. Does that not make him my enemy?’

This was as Leo had warned him. ‘The emperor took the crown in order to save the empire.’

‘Did he? Well, that was most selfless of him!’ roared the khan. ‘And I suppose he will return it once the empire is safe.’

‘His Majesty is willing to honour the terms of the agreement you made with Theodosius—’

‘We agreed annual tribute. I’ve seen nothing since the Byzantines departed. That was two years ago.’

‘He promises double tribute for the years missed while the caliph’s armies have been harrying the east.’

‘Triple.’

He could feel Davit’s indignation burning behind him. These were enormous sums of gold which Erlan had no authority to promise. But he figured that could be someone else’s problem. ‘Triple then, for the years missed. And the resumption of the agreed annual sum once the Arabs have been swept from the empire. And Byzantium is safe.’

The khan smiled, his greasy lips catching the light. ‘So now we come to the point.’

‘Besides tribute, we offer you plunder. Anything won from the Arabs is yours.’

‘That goes without saying,’ scoffed Tervel. ‘But what plunder is there to be had? The last I heard, the Arabs were eating their own shit.’

A fair point. ‘They still have weapons. Siege machines.’

‘What do I want with siege machines?’

‘Every man still alive carries things precious to him,’ continued Erlan, pressing on. ‘All this. Besides which, the basíleus promises you a further payment—’

‘This Maslama. . . he possesses a vast army. Over one hundred thousand, they say.’

‘He has fewer now. As my lord must know, many have already died at your kinsmen’s hands.’

‘Opportunists,’ grunted the khan. ‘I cannot blame them. But they’ve acted on no orders of mine. Not yet.’ He let out a long, wheezing sigh. ‘So exactly how much is it worth to your master for us to do his killing?’

Erlan named the figure, one so fantastically high that for a second, the khan’s lazy eyelids heaved themselves open a little wider.

‘The empire does not possess so much gold. It could never pay.’

‘The empire will honour its promise.’ It was an offer no man could refuse. Erlan noticed the khan didn’t try to increase the figure.

‘How many of my warriors do you hope to buy with this?’

‘All of them.’