Her phone rang and a moment later Pulaski’s voice was pumping through her earbud. ‘Amelia. I’ve got DEP on the other line. They’re checking … Hold on. The tech’s back.’ She heard some mumbling as he turned away from the speaker to a second phone. Then his voice rose. ‘The hell does that mean, “The sensors aren’t that accurate”? What does that even mean? And anyway it’s not my problem about the sensors. I want the location. Now!’

She laughed. Young Ron Pulaski had come into his own under Rhyme’s tutelage. A moment later he was back with her. ‘I don’t know what the problem is, Amelia. They’re— Wait. I’m getting something now.’ The voice faded again. ‘Okay, okay.’

Looking around the streets. Innocence, she thought again. Businesspeople, shoppers, tourists, kids, musicians, hawkers, hustlers, street people – the astonishing, unique mix of humanity that is New York City.

And under their feet, somewhere, one of the worst terror attacks in New York City history was being carried out.

But where?

‘Okay, Amelia, DEP has something for us. They’ve cross-referenced flow rates – I don’t know. Anyway, I have a location. An access room a quarter mile south of the Tunnel Three valve station. It’s at Forty-Fourth and Third. There’s a manhole about fifty feet to the east of the intersection.’

‘I’m close.’

She was already popping the clutch and skidding away from the parking space in the same way she’d arrived, though this time leaving the blue smoke behind her. She cut off a bus and a Lexus. They might have collided, avoiding her. She kept right on moving, headed south. Insurance issue, not her issue.

‘I’ll be there in one minute.’ Then corrected: ‘Okay, two.’ Because she was forced up onto the sidewalk again and braked to nudge a falafel cart out of the way.

‘Fuck you, lady.’

Unnecessary, she thought, since he’d escaped light; she might’ve knocked the cart on its ass. Had considered it.

Back on the street with a grind of metal versus curb. Then she was speeding on once again.

After Lincoln Rhyme had concluded that the unsub and his domestic terror group were planning on blowing up the water mains, he’d grown thoughtful. Then dissatisfaction bloomed in his face.

‘What?’ Sachs had asked, noting his eyes straying out the window, his brow furrowed.

‘Something doesn’t feel right about this whole thing.’ He zoned in on her. ‘Yes, yes, I detest the word “feel”. Don’t look so shocked. The conclusion’s based on evidence, on facts.’

‘Go on.’

He’d considered further, in silence, and then said, ‘The battery-bombs are packed with gunpowder. You know guns, Sachs, you know ammunition. You think that’d blow up iron pipes the size of the water mains?’