"I am perfectly calm, darling – Marcus, Marcus, I have to tell you. I know how they do it. Someone hits them on the head!'

"Someone hit youTo.

"Not hard.

My palm went to her scalp, feeling for damage. She squeaked. I pulled in a long, ferocious breath. Any man who attacked Helena Justina was as good as dead. But I had to get us out of here and find him first.

To keep her still as she thrashed about trying to talk to me, I went along with the revelations. Right! The poor fools with questions are brought here, weak from fasting. They have been drenched with cold water, inside and out, so their brains are frozen. Disorientated by fear, they fail to notice when somebody slides out of the cleft they themselves have to wriggle into.' Where was it, incidentally?

"No, I don't think anyone waits in here, or crawls in either. They would be noticed. My theory is, they lie in wait outside in the secret passage. They pull the victim feet first through the cleft – then bop them and push them back in here. The questioners have been told to hold barley cakes soaked in honey in both hands – so they can't defend themselves,' Helena burbled."And they have been told they will experience being dragged helplessly into the cleft as if pulled by the force of a river. She was shaking with cold, after lying here all afternoon. I had to take her out of this filthy cave, and quickly.

"Tell me later, sweetheart. You came through this secret passageway – now where is it?'

Then Helena helped me feel at floor level for the hole where the questioners inserted themselves. Through this crack"supernatural forces' sucked them and then – if they were lucky – the so-called gods later spat them out back into the chamber. The cleft was about two feet long and one foot high; a chubby gourmet would get stuck.

Oh pig's piss. It was too small. Hot waves of primeval fear swept over me. This was my worst nightmare. Before I came down here, I

had told myself there must be a nicely hewn corridor. Even if the secret tunnel had been made for boys and dwarves, I had imagined it as walkable – perhaps with a decent door into this chamber…

No chance. Bad luck had caught me out again. We had to lie down and squeeze out feet first through the sacred pothole.

No force of nature or divinity seized us. We lay down, used our own strength to push our feet through the gap, then wriggled our bodies after them. Helena went first, before I could stop her – but she had come in this way, so she was more confident. I felt her slip away from me, then heard muffled shouts of encouragement. I followed Helena and squeezed through into another dark cavity where it was possible only to crouch half upright. Feeling the wall on our left hand, she then pulled me for some distance along a back-breaking tunnel, to a door which led outside. With huge relief we emerged into the moonlit grove.

We straightened up and breathed the cool night air.

"Well, that's drastic – but effective! A sanctuary attendant creeps inside with a mallet. Some questioners are so badly concussed they never get over it. Dear gods, love, that could have been you.'

Helena hugged me to comfort me."It may not have been the priests. In fact, that is rather unlikely. Someone may have overheard me talking to the boys and followed me in there. When I had scrambled into the main chamber I could see nothing in the dark, so I started wriggling back to the tunnel. I heard someone there. I backed into the main chamber again but he followed. I gave his hair a good pull and poked him in the eye, I think. His blow glanced off, but I groaned very loudly and pretended to be done for.'

"You passed right out. Don't pretend otherwise.'

"Just play-acting, Marcus.'

"Cobnuts. I found you, remember. Helena Justina, you will promise me now – you will never, ever do anything that ridiculous again.'

"I promise,' she said quickly. It had all the weight of a market-trader telling me her eggs were fresh."They will never admit how they cheat, Marcus.'

"No, not even with your evidence.'

"The boys who showed me the way told me everyone at the shrine

thinks a stranger got in yesterday and stole away Statianus. Whatever happened to him was quite unplanned by the authorities.'

"So the priests don't believe the gods took him?' I asked drily.

"They had seen someone, lurking in the grove.'

"Description?'

"Just "a shadowy figure, I'm afraid.'

"Oh the old "shadowy figure" is at it again? I wonder if he's now called Phineus or Polystratus – or did somebody else trail our man here?'

"It must be someone who knows how the oracle really works,' said Helena.

"Someone who works in the travel industry would probably have a good idea!'

We tackled the priests. They released Lampon into my custody, claiming their security guards had mistaken the poet for a thief. He bravely made a joke agreeing that he had a furtive manner and communicated badly. This had my style. A few more weeks with me, and Lampon would give up scribbling, marry for love, and learn how to earn hard money boot-mending…

I accused the priests of fiddling the oracle. They accused me of blasphemy. We settled on calling what was perpetrated on questioners. 'divine manipulation in the cause of truth' – where my definitions of"divine' and"truth' differed from theirs.

To protect the good name of their oracle, they were eager to prove that some evil doer had taken Statianus from the chamber, and that the same man then attacked Helena. They could not risk other pilgrims hearing that descent into the cavern was genuinely dangerous. The official story was that only one man had ever died at the hands of Trophonius, and that he – known to be the lowlife bodyguard of a man called Demetrius – had deliberately gone into the cavern to steal gold and silver. His fate was divine vengeance, according to the priests. I told them I had a healthy respect for revenge.

After a stupid feint when the priests suggested to us that Trophonius had claimed our man for the underworld, they stopped messing with the mystic tosh and confessed themselves baffled. They absolutely denied sending in a man with a mallet to strike people on the head; I never decided whether that had happened to Statianus or if the mystery man got to him first.

Nervous about future takings, the priests now told me all they knew. Tullius Statianus came to them about a day after Helena and I

met him in Delphi. Somebody had told him of a rocky short cut, so he had made good time.

At the shrine, Statianus had claimed he was in danger. The priests simply assumed that like many of their customers he was haunted by demons – figments of a tormented imagination. Thinking no more of it, they prepared him with the rituals and sent him into the chamber. According to them, when the bronze trapdoor was opened again after the regulation period, instead of finding him in shock on the floor, he was simply gone.

I believed them. There would have been no benefit to them in lying. They needed to pull questioners out after their ordeal, alive. Dead men would only deter future trade.

Only after they found that Statianus had vanished, had attendants talked among themselves and recalled sightings of the unknown man in the grove. By then it was too late. Nobody had spoken to him at the time. Nobody had seen him since.

"Has a travel company from Rome, called Seven Sights and led by a man called Phineus, ever brought clients to this oracle?' Occasionally. The priests discouraged it. Yourists in general took one scared look, then declined to carry out the ritual. There was no money in their visit and it wasted time."Still, you do know Phineus. Could he be your skulking man?' Too far away to tell."Anyone ever met his sidekick, Polystratus?' Not that they were aware of.

Exhausted and frustrated, we had to give up. We had searched; we had asked the right questions. If anything new was discovered, messages would be sent to the governor. Our business at the oracle was over.