'Hmm,' droned Artemis, unconvinced. Passers-by would have been amazed to hear the large Eurasian refer to the boy as sir. This was, after all, the third millennium. But this was no ordinary relationship, and these were no ordinary tourists.

They were sitting outside a kerbside cafe on Dong Khai Street, watching the local teenagers circle the square on mopeds.

Nguyen was late, and the pathetic patch of shade provided by the umbrella was doing little to improve Artemis's mood. But this was just his daily pessimism. Beneath the sulk was a spark of hope. Could this trip actually yield results? Would they find the Book? It was too much to hope for.

A waiter scurried to their table.

'More tea, sirs?' he asked, head bobbing furiously.

Artemis sighed.

'Spare me the theatrics and sit down.'

The waiter turned instinctively to Butler, who was, after all, the adult.

'But, sir, I am the waiter.'

Artemis tapped the table for attention.

'You are wearing handmade loafers, a silk shirt and three gold signet rings. Your English has a tinge of Oxford about it and your nails have the soft sheen of the recently manicured. You are not a waiter. You are our contact, Nguyen Xuan, and you have adopted this pathetic disguise to discreetly check for weaponry.'

Nguyen's shoulders sagged.

'It is true. Amazing.'

'Hardly. A ragged apron does not a waiter make.'

Nguyen sat, pouring some mint tea into a tiny china cup.

'Let me fill you in on the weapons status,' continued Artemis. 'I am unarmed. But Butler here, my…ah…butler, has a Sig Sauer in his shoulder holster, two shrike throwing knives in his boots, a derringer two-shot up his sleeve, garrotte wire in his watch and three stun grenades concealed in various pockets. Anything else, Butler?'

'The cosh, sir.'