22
In the early hours of the morning the CSM had peered again at the mould of the footprints and tended to agree with Flea: the marks did look as if they could have been made by a mooring spike. The POLSA turfed out at first light and marked up a stretch of canal to be searched. Teams were given waders and a two-mile section to check either side of where the Yaris had been parked. But the Thames and Severn canal had a peculiarity that the standard search teams couldn’t deal with. Two miles of it ran completely unseen and unnoticed in a tunnel deep under farmland and forests. The Sapperton tunnel. Abandoned and deeply unstable. A two-mile death trap. Nothing more, nothing less. Only one unit was trained to deal with a search like that.
By eight o’clock more than forty people had gathered at the westerly entrance to the Sapperton tunnel. On the crenellated parapet above the opening, hoping for a glimpse of what was going on below, stood about twenty journalists and a handful of plainclothes MCIU officers. They were all looking down to where Flea and Wellard were thigh-deep in the black, stagnant canal water, readying their little Zodiac inflatable, loading it with what they needed to enter the dripping tunnel – communications systems and air cylinders.
The Underwater Search Unit knew a little about the tunnel already. They’d used it years ago as part of their confined-space search training. The trust that owned the canal had given them structural information: the tunnel was seriously unstable; it ran dangerously close to the Golden Valley railway line, and every time a train went past the great slabs of fuller’s earth and oolite that made up the roof were shaken. The trust wanted to make it clear that they couldn’t guarantee what was going on in there: it was too dangerous to survey properly. What they could say for sure was that a massive, impassable rockfall blocked at least a quarter of a mile of the tunnel. It was vaguely visible from the surface as a long necklace of tree-filled craters and started not far from the easterly entrance, extending a long way into the tunnel. It had been relatively easy for two of Flea’s men to put on hard hats and wade the couple of hundred yards to the eastern end of the rockfall and push a probe through in the faint hope it’d come out the other side to be picked up by a team coming from the westerly entrance. Now, though, they were going to have to cover the tunnel from the other end and go a mile and a quarter underground before meeting the rockfall from the other side. And hope none of the unstable rocks chose to shake themselves loose as they did it.
‘You sure about this?’ Caffery was sceptical. Dressed in a padded North Face jacket, with his hands thrust into his pockets, he peered past them into the gloom. At the rubbish and bits of trees floating on the inky surface. ‘Sure the HSE are happy with it?’
She nodded, didn’t meet his eye. Truth was, the HSE would have kittens if they knew what she intended doing. But the only way they’d find out was when the bastard press hounds got the news out there, and by that time the search would be over. And they’d have found Martha. ‘Yeah,’ she said. ‘I’m sure.’
She kept her eyes just south of his as she spoke. Thought that if he saw inside them he’d know she was following that ineffable thing. A hunch. And straining at the leash to do it. Because now finding Martha wasn’t just about putting a pretty feather in the unit’s cap. It meant more to her. It meant making amends for not being stronger earlier.
‘I don’t know.’ Caffery shook his head. ‘A maybe match on the cast and that’s all? It’s kind of a flimsy justification to be putting officers through this.’
‘We know what we’re doing. I won’t be putting either of us at risk.’
‘I believe you when you say that.’
‘Good. Nice to be trusted.’
The journey into the canal was slow. They pushed the boat carefully, guiding it past obstacles, past broken barges. Shopping trolleys stuck up out of the muck like skeletons. She and Wellard wore the dry suits they used for swift water rescues, with red hard hats and the wellies that had built-in steel toecaps and shanks. Each carried a small escape set: rebreathers mounted on their chests that would give them thirty minutes of clean air if they ran into a bad pocket of gas. They went in silence, using the beams from their head torches to scan the sides and bottom of the tunnel.
It had been designed for the canal lightermen to ‘leg’ the barges through: lying on their backs, pushing with their feet against the ceiling to move the tons of coal and wood and iron along the two miles of darkness. In those days the tunnel roof would have been claustrophobically close to the water surface and there would have been no towpath: Flea and Wellard could only walk upright now because the canal level had dropped so much that it had revealed a narrow ledge of sorts on one side that they could use.
It was warm down here – the biting cold on the surface couldn’t penetrate so deep. The water wasn’t frozen. In places it was so shallow it was little more than a thick black sludge around their ankles.
‘It’s just fuller’s earth.’ They were five hundred yards inside when she spoke. ‘The stuff they make cat litter out of.’
Wellard stopped pushing the Zodiac and shone his torch up at the roof. ‘This isn’t kitty litter, Sarge. Not with the pressure it’s under. See those cracks? Those strata are massive. And I mean massive. One of them came down it wouldn’t be like cat litter, it’d be like having a Transit van fall on you. Could seriously ruin your day.’
‘Don’t tell me you’ve got a problem with this?’
‘No.’
‘Come on.’ She looked at him out of the corner of her eye. ‘Tell me. Are you sure?’
‘What?’ he said irritably. ‘Of course I’m sure. The Health and Safety Exec hasn’t got its rod shoved that far up my arse. Not yet.’
‘There aren’t any guarantees.’
‘I hate guarantees. Why do you think I’m in this unit?’
She gave him a grim smile and they looped their gloved hands into the handles on the Zodiac, leaning against the inertia of the boat until it loosened from its spot. It lurched forward, rocking from side to side in the black water. When it was settled between them they resumed the slow march into the tunnel. The only sounds were the slosh of their boots in the water, their breathing and the tiny ping of the gas detectors strapped to their chests, a comfort signal that the air was clean.
Parts of the roof were brick-lined, others had been left exposed. Their head torches played over strange plants bursting through crevices. From time to time they had to pick their way over falls of clay and fuller’s earth. Every few hundred yards they came to an air shaft: a six-foot-wide hole sunk more than a hundred feet from the surface to allow air in. The first hint they’d get of an approaching shaft would be a strange silver glow in the distance. Slowly, as they progressed, the light would get brighter and brighter, until they could switch off their torches and stand under the holes looking upwards, their faces bathed in the white sunlight slicing down through the plants that clung to the walls of the shaft.
It would have been easier to explore the tunnel by dropping in through these air shafts, if each hadn’t been protected by a vast rusting grille at the bottom. Debris had been able to fall through the grilles. Huge piles of ancient rotting leaves, branches and rubbish sat under each. One had been used by a livestock farmer to dump animal carcasses. The weight of the dead meat had caused the grille to give way and tip a pile of stinking animal bones into the canal. Flea stopped the boat next to it.
‘Nice.’ Wellard covered his nose and mouth. ‘Do we have to stop here?’
She ran the beam across the water. Saw bones and flesh and half-eaten animal faces. She thought about the jacker’s letters: I’ve rearranged her a little . . . Slowly she stirred the mess using the steel toecap. Her foot touched rocks and old tins: she hit something big. Reached in and pulled it out. It was the blade from an old-fashioned plough. Probably been there for years. She discarded it.