maybe two. Need waterproofs and a mask. Another day, if you want to know the reason.’
‘What reason?’ asked Bryant. ‘What are you talking about?’
‘Reason for all this upset. The water is where it began.’
To Bryant, it seemed the most inhospitable place imaginable. He wondered how the tramp could have slept on the platform without being besieged by nightmares.
‘Come on, the rain’s getting harder. Tunnel fills up fast. Drains off the Heath, through clay and brick, thousands of gallons in seconds. Get swept away and no one will ever find you again.’
Tate started to climb back up. He pulled himself out of the drain with ease, extending his shattered hand to Bryant. The pair were bonded by a secret now.
Back in the alley, he produced a muddy piece of card from his jacket and held it up. ‘You need this.’
On it was printed a faded diagram designed like a Tube map, overlaid with the kind of Helvetica lettering popularized during the War. Instead of underground branch lines, it showed the paths of tributaries, each one variegated and named. Tate was holding the plan to a network of conduits. He tapped a calibrated thick line with his blackened forefinger. ‘The Fleet. Each dot is a lock. Each line is a sealed gate.’
Bryant dug out his reading glasses and took a squint. ‘According to this, you can’t get as far as the Regent’s Canal.’
‘No, but you can branch off, all the way up to the York Road Basin. It was fine during the summer, you could walk along it, armed with the right keys. Now you have to divert each of the cross-courses as you go. As you said, the Water Board knows. They got the equipment. But I got all the keys.’
‘You’ve done it?’
‘A few of us.’
Bryant squinted through the drizzle that softened Tate’s weathered face. ‘Who are you?’ he asked quietly. Tate’s lips thinned, but a moment later the smile had vanished.
‘I’m nobody,’ he whispered sadly.
35
* * *
HUMAN NATURE
‘I think our killer is using the underground tunnels,’ Bryant explained, obliviously poking pedestrians with the tines of his umbrella as they dodged the puddles in Kentish Town High Street. ‘He enters the alley from the back gardens and goes down into the water conduit. It passes right under the road and connects to the backs of all the houses on the east side.’
‘Why would anyone go to so much trouble?’ May was having difficulty keeping up with his partner this afternoon. A sense of angry urgency invaded Bryant whenever he was faced with the fallout from a preventable death. He and John had spent most of Friday with the shocked residents of Balaklava Street. Now they had left Aaron alone with his guilt in a searched, emptied and fingerprinted house, minus the person who had brought the rooms to life, and the world was expected to turn as usual. In the months following a death, the survivors saw small cruelties wherever they looked. It disturbed Bryant to recognize that the unit should have taken matters more seriously from the outset, and shamed him that they had achieved so little. It was the only time in the investigation when he had displayed any other emotion than a ghoulish enthusiasm. His revenge was to ignore his age and infirmities, to work harder than ever. It was when he needed to be watched most carefully.
‘So that no one sees anything unusual in the street, obviously. Look how enclosed and overlooked it is. If you’re well known in the area, witnesses are likely to remember you. It’s someone Tate and probably all the others know by sight. That’s why Tate didn’t seem frightened when I talked to him. It’s the unknown that scares people, the faceless stranger who attacks for no logical reason, because he’s on drugs, or drunk, or just disturbed.’ He thrust a crumpled paper bag at May. ‘Have a pear drop.’
‘You’re taking a leap in the dark with this,’ warned May. ‘There’s no reason to make such an assumption. The tramp has a history of mental problems, you said so yourself. He’s an unreliable source of information. It might even be him.’
‘And what would his motive be? Hang on, I want to get some sausages.’ Bryant dragged his partner into the butcher’s and tapped the cabinet. ‘Are those Gloucester Old Spots fresh? They don’t look it.’
‘The oldest motive in the world,’ May insisted, trying to concentrate. ‘They have something he hasn’t. Homes, money, security.’
‘Then why doesn’t he take anything? And why would he