'This would be a high-class building, originally, George?' Caroline asked.
'It'd need a fair bit of study to work out exactly what it was,' George said. 'Private home? Municipal building? You're right, though, definitely not a worker's cottage.'
Carefully, they picked their way through rubble and cobwebs. Ahead, maybe twenty yards away, was a wall of solid, compacted stone and earth. 'No way forward,' Aubrey said.
'Hello. What's this?' George squatted on one knee, right where the edge of the vault met the floor, and inspected a slab of stone – low and about six feet long, running parallel to the line of the vaulted ceiling.
'A bench?' Aubrey guessed.
'Don't think so. Can you lend a hand?'
Caroline took the lantern. Aubrey joined George.
'Now,' George said, 'let's see if we can shift this thing.'
'Shift it? Something that's been sitting here for two thousand years?'
'If I'm right, it was meant to be shifted.' George pushed, and hissed with effort.
Aubrey put his shoulder to the stone and added his weight. 'No good.'
'Let's try the other end,' George said, wiping his hands together.
Aubrey lost some skin from his knuckles, but the stone did indeed slide aside. Panting, he looked down into a narrow flight of stairs.
'Now we're onto something,' George said, beaming.
'How did you know, George?' Caroline eyed the gap into darkness.
'Something I read. Some of these old Roman places had secret shrines underneath.'
A small bell rang in the back of Aubrey's mind, something he'd come across in one of Professor Mansfield's recommended books. 'So these weren't the ostentatious, showy sort of public shrines?'
'These were private, or only known to a small group. Not official, you see. These people were worshipping something that would get them into trouble if it was widely known.'
'They used them for magic, too,' Aubrey said.
'Outlawed magic.'
'I hadn't heard that,' George said, 'but it would make sense. Fortune-telling, divination, magic like that went hand-in-hand with some of this sort of worship.'
The possibility of discovering traces of ancient magic removed any doubts Aubrey had about this side expedition. ' Well, I can see that you're eager to inspect this shrine, George. I suppose we can spare the time.'
'You're awfully keen, all of a sudden,' Caroline said.
'Just being accommodating.'
'That's why I'm suspicious. What about being careful?'
'Ah. Yes. George?'
'Looks sound enough. If it hasn't fallen down in two thousand years, I don't think it's about to collapse on us now.'
'You mentioned magic, Aubrey,' Caroline said. 'Any danger there?'
'Let me see.'
Aubrey stood for a moment and extended his magical awareness.
It was like listening hard for faint sounds. The world seemed to go away as he focused. Without realising it he turned slightly from side to side, as a sunflower turns to follow the warmth of the sun.
'Aubrey?' Caroline said.
He opened his eyes. 'There's magic down there. Weak, a trace of a residue, I'd say.'He rubbed his hands together, as if they had dirt on them. The magic was of a flavour that he'd never encountered before. Rough, coarse, even, but it held a ghost of power. In its day, it was probably impressive. Now, all he was feeling were echoes across the centuries.
'Is it dangerous?' Caroline asked.
'No. Probably not. Almost certainly not.'
'Hardly reassuring, that.' George lifted his pry bar.
'I hope this thing doesn't come in useful.'
Aubrey bit his tongue. If magic were involved, a pry bar probably wouldn't be much help.
'I'll go first. Caroline, can you take the lantern and come next? George at the rear.'
The third step was where Aubrey started to feel uneasy.
It was a gradual thing. He shivered on step three, but he told himself he was imagining it. Step four added to his sense of disquiet, but he decided he needed more proof.
He took the next step down – five – and at that moment Caroline, behind him, said, 'Oh.'
Aubrey stopped. 'You felt it too?'
'Felt what?' George asked.
'Yes,' Caroline said. 'It was like stepping into an ice bath.'
'So I wasn't imagining it.' The chill he'd encountered at first was now swirling around his calves, biting right through the fabric of his trousers. The cold was ominous enough, but it was the swirling that made him even more alert. Something was moving down there.
'Wait a moment.'
Slowly, he stepped onto the sixth stair. The cold rose to his knees. 'Brace yourselves,' he said. 'It's freezing down here.'
By the time he reached the bottom, he was totally immersed in frosty air. His breath steamed and he shivered. Any exposed skin was nibbled by icy teeth.
Aubrey touched his cheek, then scratched it. Everything about the place made him alert – the shadows, the slightly dank smell, the sound of water trickling nearby – but his caution had nothing concrete to fasten on. The unfocused nature of the potential danger made things worse, and he clenched his hands into sweaty fists.
The room was small – two or three yards long, half that wide. The blocks of the walls, ceiling and floor were roughly dressed. At the far end stood a stone table – a slab resting on a solid base.
Caroline joined him. She'd wrapped her arms around herself and she held the lantern close for its warmth.
'Why is it so cold?'
George tapped a wall with his pry bar. His voice was harsh, strained. 'So this is our hidden shrine. Any clues, Aubrey?'
'Don't move for a moment. I must think.'
Hostility. Aubrey could feel it oozing from the walls. It was similar to the concentrated emotion spells perfected by Caroline's father, but cruder. He wondered, briefly, if Professor Hepworth had gone back to Roman roots for inspiration for his particular branch of inquiry.
The stone table shook.
Aubrey shuffled back a few steps. He felt Caroline's hand on his shoulder, then George's reassuring bulk on his left. His heart threatened to crack a rib with its pounding.
'We're intruders,' he said through a throat that was suddenly hoarse. He opened and closed his fists, realising they were aching from being clenched so hard.
'Intruders?' Caroline breathed. He glanced to see that she was holding out her hands in front of her, as if feeling the texture of the air.
'This is a holy place,' he said. 'A secret holy place. Guardian magic, I'd expect.'
'What can you do about it?' George said.
'We can try to convince the place that we're harmless, before it decides to use more active deterrents than just fear and cold.'
'How do we do that?' George asked.