‘And they are still digging?’ the Baron asked Grant as they moved on. ‘The Apollo had not risen when your Simon came to S. Tommaso? He is then a contemporary resurrection?’

‘A latter-day Lazarus,’ fluted Mr Mailer. ‘But how much more attractive!’

Somewhere in the dark Kenneth echoed his giggle.

Sophy, who was between Alleyn and Grant, said under her breath, ‘I wish they wouldn’t,’ and Grant made a sound of agreement that seemed to be echoed by Major Sweet.

They continued along the cloister of the old church.

It was now that Baron Van der Veghel developed a playful streak. Holding his camera at the ready and humming a little air, he outstripped the party, turned a corner and disappeared into shadow.

Mr Mailer, at this juncture, was in full spate. ‘We approach another Etruscan piece,’ he said. ‘Thought to be Mercury. One comes upon it rather suddenly: on the left.’

It was indeed a sudden encounter. The Mercury was in a deep recess: an entrance, perhaps to some lost passage. He was less strongly lit than the Apollo but the glinting smile was sharp enough. When they came up with him, a second head rose over his shoulders and smirked at them. A flashlight wiped it out and the echoes rang with Baron Van der Veghel’s uninhibited laughter. Lady Braceley gave another scream.

‘It’s too much,’ she cried. ‘No. It’s too much!’

But the elephantine Van der Veghels, in merry pin, had frisked ahead. Major Sweet let fly anathema upon all practical jokers and the party moved on.

The voice of the subterranean stream grew louder. They turned another corner and came upon another railed well. Grant invited them to look up and there, directly overhead, was the under-mouth of the one they had already examined in the basilica.

‘But what were they for,’ Major Sweet demanded. ‘What’s the idea? Grant?’ he added quickly, apparently to forestall any comment from Mr Mailer.

‘Perhaps,’ Grant said, ‘for drainage. There’s evidence that at some stage of the excavations seepage and even flooding occurred.’

‘Hah,’ said the Major.

The Baroness leant over the rail of the well and peered down.

‘Gerrit!’ she exclaimed. ‘L-oo-ook! There is the sarcophagus! Where Simon sat and meditated!’ Her voice, which had something of the reedy quality of a schoolboy’s, ran up and down the scale. ‘See! Down there! Belo-oow.’ Her husband’s flashlight briefly explored her vast stern as he gaily snapped her. Heedless, she leant far over the railing.

‘Be careful, my darlink!’ urged her husband. ‘Mathilde! Not so far! Wait till we descend.’

He hauled her back. She was greatly excited and they laughed together.

Alleyn and Sophy approached the well-railing and looked downwards. The area below was illuminated from some unseen source and the end of a stone sarcophagus was clearly visible. From their bird’s eye position they could see that the stone lid was heavily carved.

As they looked, a shadow, much distorted, moved across the wall behind it, disappeared, and was there again, turning this way and that.