Finally the torch picked out a faint glitter. She called back again, 'I'm at the cave.'

Paulo's voice came back, echoing: 'OK.'

She jumped down to the floor and looked around. There it was, as she remembered. The jagged, glittering stalagmites, sticking up from the uneven floor like teeth in a shark's mouth. The drip, drip of water and the occasional rasp of pebbles moving. But not the other noise. The generator wasn't on. That meant the men weren't in there. It was safe to look around for now.

According to the cavern plan Li had memorized, the far wall was the nearest point to the buried factory. So that was where she needed to explore. She picked her way round the edge of the cave. It was like tiptocing round a room filled with sharp ornaments. She reached the far wall and the cave roof opened up into a hole.

A cold light breeze touched her right ear and the top of her head. A draught meant a hole. Li ran her torch over the rock wall. It went on up, beyond where her light could reach. What was it? A shaft? Only one way to find out where it went. She would have to climb.

The rock was quite smooth, but her experienced eye picked out a few hand- and footholds. She'd definitely need her bare fingers, though. She peeled off her gloves and put them in her pocket, then felt the wall. How would she hold the torch? Could she climb in the pitch dark?

She would have to. Her fingers closed on the switch. They wouldn't obey her. She didn't want to turn off the torch, feel the darkness close in.

She tried shutting her eyes. There, that was what the dark was like. It would be no worse than that.

She switched off the torch and slipped it into her pocket. Then she opened her eyes and tilted her head up.

Far above, there was a tiny patch of light. It was about the size of a coin, but it was a patch of light nevertheless. It was a way out, near the factory. She definitely had to investigate.

Li gave her fingers a quick stretch and clenched her fists a few times to get the circulation going. Then she put her hands on the wall.

Once she started, a kind of calm settled on her. Concentration drove all fears out of her head. She just went steadily up.

The tunnel became narrower, until the rough rock wall touched her back. She leaned into it and pushed herself up with her legs. The patch of light became bigger and the draught of fresh air was getting stronger, banishing the smell of wet rock and mud.

There was something else: one edge of the hole was straight and smooth. Li reached the top and found a grey plastic drainpipe ran across the top of the shaft like a bridge. By the drainpipe was a ledge. Li pulled herself up and stretched her aching limbs. Above her was a small crack in the rock, about fifteen centimetres wide far too small to climb through, but big enough to let light in.

The drainpipe came horizontally out of the crack and went down a tunnel. Li shone her torch down it. It was wide enough to crawl down on hands and knees. Well, she might as well see where it went.

Suddenly her torch picked out a dead squirrel; it had died quite recently, she thought. It must have fallen down the fissure. She pushed it aside with her elbow. Under it were dead beetles. She looked around. The tunnel was littered with dead squirrels, field mice and voles.

This was odd. She might have expected to find one or two dead creatures, but all these? And what was this pipe?

Alex waved his arms and paced up and down the tunnel to get warm. He'd actually had a mad moment when he'd been excited about going into hiding. He didn't envy Hex and Amber their upmarket lodge. Living off the land was far more his style. After all, his dream for the trip was cooking mussels and c.o.c.kles in a fire pit on the sh.o.r.e of the Kyle. But waiting for Li in a dark, freezing tunnel was something else.

Even Paulo, who had a high threshold for discomfort and cold, was stamping his feet. He looked at his watch. 'I wonder where she is.'

'She's only been gone about fifteen minutes,' said Alex.

'If something happens to her, how do we get her out?' asked Paulo.

Paulo didn't normally worry like this, thought Alex. The cold and dark must be getting to him too. But all they could do was sit and wait. 'At least down here we're not likely to run into the gamekeepers,' he said. 'But this third man we've seen bothers me. Who is he?'

'I've been thinking about that,' said Paulo. 'I've got a theory. Those gamekeepers seem to have the run of the place. They can burn down a bothy if they want to. They broke down the front door of the hostel and if they'd shot us in there, there would have been a h.e.l.l of a lot to explain. They didn't seem worried that anyone would find out. They can do what they like on the laird's land, they're untouchable. And why? Because the laird is also in on it.'

Alex spoke slowly. 'So you think the guy with the kilt that Hex saw was the laird?'

Paulo nodded.

21.

THE L LAIRD'S K KINGDOM The pheasant pens looked like tennis courts, roofed over with netting. 'Predators are a problem so we keep the birds in these pens.' The laird's accent had a faint trace of London's East End, but in his blue-green kilt with walking boots and a rough armystyle jumper, he looked the part as he showed newly arrived guests around the shooting facilities.

Hex was staring at the laird's kilt, until Amber nudged him to look at the birds. He glanced around. Birds scratched around the muddy earth floor, pecked at grain, shook the recent rain from their feathers and stared apprehensively at the group of humans watching them through the fence. Two middle-aged couples were also in the party.

Hex turned away from the pen. 'That bird's looking at your hat,' he said.

'Then he knows good style,' replied Amber. She was still wearing the low-slung plus-fours and corn-coloured cap. Hex had rejected the plus-fours and gone for a checked shirt and distressed jeans. The 'distressing' was absurdly modest a small hole on the thigh darned by a Jermyn Street tailor.

'Hey, a fellow American? Where are you from?'

'Boston, Ma.s.sachusetts.' Amber shook hands with the two couples. Their tweed skirts and trousers had knife-edge creases, as though they had only recently been taken off the hangers in the shop.

'OK,' called the laird. 'That's all there is to see outside. It's time to go in and I'll show you the gun store.'

He led the way with easy strides across the yard. They dodged round staff members going to and from the farm buildings. Earlier on the tour, the laird had shown them the feed room, with tall steel bins containing sweet-smelling grain, the fertilizer room, where drums of organic fertilizer stood bearing hazard stickers. Amber glimpsed other rooms as they went past: a workshop, a rest room with a kettle and mugs, a wet clothes room with a daily timetable for checking livestock. But one door remained locked. Its paintwork was just as scarred as the others' so it was clearly used. Just not while people were watching, perhaps.

Hex was looking at the laird's kilt again. He'd seen a lot of tartans that afternoon and he'd researched one in particular. A blue-green, like that one. It was a modern design, not a traditional one. A tartan made up for tourists who wanted a piece of Scottish history but had no real ancestral links. That suggested he was trying to fit in, like a chameleon. Was he the man who had tried to kill them? Hex had only caught a brief glimpse of him.

As they headed for the back entrance, a quad bike puttered into the yard. Amber saw the missing panel first, then the rider. The gamekeeper with the pockmarked face and the scar. She looked away quickly and seized Hex's arm, nuzzling his ear.

Hex was startled, then heard her whisper, 'They've found the quads.'

'Would you just excuse me a moment, ladies and gentlemen,' said the laird. He walked over to the gamekeeper, his kilt swinging.

Hex turned and murmured in Amber's ear. 'Let's go.' They walked into the lodge through a dark pa.s.sage and emerged in the main entrance hall. It was an impressive s.p.a.ce. The staircase was huge, like Grand Central Station's, and edged with stone bal.u.s.trading. Crimson leather sofas were cl.u.s.tered around a magnificent stone fireplace the height of a railway tunnel. One of the doors next to the fireplace swung open and a man in a butler's uniform came through, a tray containing c.o.c.ktails poised on one outstretched palm.

Amber and Hex had hoped to slip away on their own, but the other guests on the tour were following.

'We've got to get rid of them,' muttered Hex.

Amber let out a lascivious giggle and hooked her arm around Hex's waist.

'I think we should leave these young people to explore on their own,' said a woman's voice behind them.

Amber steered Hex up the stairs. 'Perhaps see you later,' chuckled one of the men.

On hands and knees, Li led Paulo and Alex down the tunnel with the drainpipe. She had found it joined up with one of the tunnels near the entrance a much easier route than squirming through to the stalagmite cavern and up the shaft.

'It's quite long,' said Li, at the front, 'and eventually it goes into- Ah, here we are.'

She shuffled to one side and the others hunkered down beside her. The crevice above them let in light, so they switched off their torches to save the batteries.

Paulo knelt close to the drainpipe and sniffed it.

'Don't get high,' said Li.

'Diesel fumes. This is the exhaust pipe for the generator. They've been clever installing it near this pothole so they wouldn't have to build chimneys. And this is their only ventilation hole, which is why they've kept the fumes contained in this pipe.'

Alex stood up and peered into the crevice where the drainpipe disappeared. 'This is the factory?'

'It must be,' said Li. 'It's in the right place.'

'I wonder how far this crevice goes.' He switched his torch on and shone it into the hole.

'Well?' said Li.

'Can't see much... some bulky shapes, lots of gla.s.s pipes... It's really close.'

Paulo tapped him on the shoulder, offering his mobile. 'Take a picture.'

'I would if I had very long, slim fingers,' said Alex, 'but I can't reach down the hole.'

Li took off her rucksack and rummaged inside. She brought out a wire coathanger. 'How about this? It got into my bag along with my Gore-tex jacket.'

'Excellent,' said Paulo. He straightened it out and handed it to Alex.

Alex made a rough cage for the phone and set it to take several frames on a timed exposure. He pa.s.sed it gently through the crevice into the container. He slid it to the limit of his reach, then heard several clicks as it took the pictures. He pulled it back out, unthreaded the case and inspected the results. A slow, satisfied smile broke out over his face. He handed the phone to Li and Paulo.

The two friends gasped.

The pictures showed red walls with steel ribs; royal-blue drums; several items of gla.s.s, like a complicated laboratory. There was no doubt this was the underground drugs lab.

Paulo was thinking. 'You know what they do? I bet they bring the ingredients here inside the carca.s.ses. When they get an order they take the finished product to the bothy to be counted and bagged, then transport it in a carca.s.s to the coast.'

'Why do they bother with the bothy?' said Alex. 'They could do everything underground.'

'Ventilation?' said Paulo. He squinted at the picture. 'It looks very crowded in there. There must be a lot of dust when they're measuring pills out. The bothy's bigger, with better ventilation. Even there, we saw they had to use masks.'

Li nodded. 'It's very clever. Everything's hidden the factory's underground and every time they move something it's inside a carca.s.s. No one need ever see anything unusual.'

Paulo looked at the picture on the phone. 'But how long did it take them to build all this? Surely that would have attracted attention.'

'Let me see that,' said Alex. Paulo handed him the phone. Alex looked at the picture. 'Ah yes, I thought so. They didn't build it.' He pointed to the steel ribs on the walls. 'It's one of those transcontinental containers, like they carry on ships and lorries. They must have dug a great big hole and buried it. Simple and quick.'

Li nodded. 'That's why we found such a big area when we paced it out with the metal detector.'

'Those blue drums,' said Paulo. 'We found pieces of them in the bothy. They obviously contain the raw materials. I wonder where they dispose of them? They must have quite a collection.'

Li looked at her watch. 'Ten minutes and we need to go to the surface to call the others.'

Alex looked at the pipe snaking into the factory. 'This is a brilliant discovery, Li.'

Paulo nodded. His mind was already working. 'If the others can find out when the pick-up is, there's a lot we can do with this.'

22.

OLD F FRIEND.

Hex pulled back the portcullis on the lift and stepped out into a deep-pile crimson carpet. They turned down the corridor towards their suite. It was time to call the others.

The other lift in the pair arrived and they heard a rattling sound. The iron portcullis was stiff. There was also a voice a rather distinctive one. 'I've been abseiling, potholing, kayaking...'

Hex and Amber froze.

'Really?' said a male voice.

'Oh yes. My horse bolted with me on the moors and I had to navigate off a foggy sea using just my compa.s.s.'

Hex looked at Amber with an expression of pure fear. 'Tiff,' he mouthed.

'Wow, you're a really adventurous girl,' said the male voice.

'She's showing off,' whispered Amber.

The portcullis finally snapped open.

Amber and Hex shared the same thought. They did not want to run into Tiff right now. Hex noticed a door-shaped outline running across the picture rail and down through the dado. It must be one of the secret servants' entrances. As the voices came towards them he pushed it open. Amber practically pushed him through to get out of the way in time.

They were in a windowless stone stairwell lit by a bare light bulb, in marked contrast to the opulcnce they had just left behind. Sounds and smells of cooking wafted up from below.

Hex looked around, curious. 'How the other half live.'

Amber pulled the door open a crack and peered back into the luxury world. 'They've gone.'

They went back into the corridor. Their suite was just a few doors along.

Amber closed the door and locked it. Now, finally, they were alone.

'What's she doing here?' Spluttered Hex. He unclipped the phone from his belt and waved it around, looking for the best signal.

Amber belly-flopped onto a ma.s.sive four-poster bed. Everything in their suite was on a grand scale. Their two bedrooms were each the size of an entire apartment. 'She's changed her tune.' Her voice shifted into Tiff's nasal tones. 'My stallion bolted, I navigated out of a sea fret using just my sense of smell.' 'My stallion bolted, I navigated out of a sea fret using just my sense of smell.' Amber's expression was furious. 'She hated every minute she spent with us. Now she's a born again Lara Croft.' Amber's expression was furious. 'She hated every minute she spent with us. Now she's a born again Lara Croft.'

Hex needed a stronger signal and moved to the window. It was starting to rain again. 'We need to keep out of her way. She could blow our cover.'

Amber traced the pattern of the heavy brocaded bedspread with her finger. 'If she carries on boasting like that, she'll blow her own cover. If the gamekeepers hear her it'll be obvious she was at the hostel.'