‘Exactly. The crime scenes are in places where the flooding would cause the most damage if the pipes blew.’

Rhyme turned to Pulaski. ‘Thanks, rookie.’

‘You’re welcome. I’m still not sure what I did.’

‘You thought those scars around the numbers were waves, not scallops. And they were. Waves! That put me in mind of the flood and Noah. Now we’ve got an apocalyptic theme going. This changes everything.’ Rhyme scanned the evidence chart. His thoughts fell hard, clattering like the sleet outside. Good, good. Moving along.’

Mel Cooper asked, ‘How would the unsub know where the vulnerable spots would be, though? The water grid charts’re classified.’

It was then that Rhyme’s mind made one of its unaccountable leaps. They didn’t happen often; most deductions are inevitable if you have enough facts. But occasionally, rarely, an insight gelled from the most gossamer of connections.

‘The bit of beard – the one you found here, by the shelf when Eleven-Five ruined my favorite single-malt.’

Eyes bright, Sachs said, ‘We thought it was cross-contamination. But it wasn’t. The beard came from Unsub Eleven-Five himself when he broke in here. Because he was the one who killed the worker last week.’

‘To get the keys to his office,’ Rhyme said.

‘Why? Where did he work?’ From Ron Pulaski.

‘Public works, specifically, Environmental Protection,’ Rhyme muttered. ‘Which runs the water supply system. The unsub broke in and stole the water grid charts to know where to plant the IEDs. Ah, and the blueprint fiber that the perp left at the scene in Pam’s apartment, when he attacked Seth? That was from the plans.’

Rhyme looked again at the map of the city. He pointed to massive Water Tunnel 3, the biggest public works project in the history of the city. It was one of the most massive sources of water in the world. The tunnel itself was too far underground to be vulnerable. But there were huge distribution lines running from it throughout the city. If they were to blow, billions of gallons of water would gush through Midtown and lower Manhattan. The results would be far worse than any hurricane could produce.

‘Call Major Cases,’ Rhyme ordered. ‘And Environmental Protection and the mayor. I want the water supply shut down now.’

CHAPTER 61

‘How are you feeling, Uncle Matthew?’

‘All right,’ the man muttered. ‘In the hospital you could count on one hand the number of people who spoke English. Lord have mercy.’

That, Billy was sure, wasn’t accurate. And was typical of exactly the attitude that the AFFC had to guard against. The issue wasn’t that the hospital workers didn’t speak English; of course they did. It was that they spoke it with thick accents, and not very well. And that, like the color of their skin, was proof that they came from cultures and nations that didn’t represent proper values. And that they hadn’t bothered to assimilate.