Hale, of course, might have simply broken into the four locations without the fiction of the Watchmaker, but if anyone had seen a burglar or noticed anything missing or out of order, the question would have arisen: What was he really up to? So he’d created layers of motives for the break-ins. His original plan was simply to pretend to be a serial killer to get access to the four locations he needed to, sacrificing his unfortunate assistant, Vincent Reynolds, in order to convince the police that the Watchmaker was just who he seemed to be. But then in mid November, an organized crime contact in the area called and told him that an NYPD cop named Dennis Baker was looking for a hit man to kill an NYPD detective. The mob wouldn’t touch killing a cop, but was Hale interested? He wasn’t but he immediately realized that he could use Baker as a second complication to the plan: a citizen getting revenge against a crooked cop. Finally, he added the wonderful flourish of the Delphic Mechanism theft.

Motive is the one sure way to get yourself caught. Eliminate the motive, you eliminate suspicion. . . .

Hale now stepped to the front flower arrangement in the conference room and adjusted it the way any diligent soldier would do—a soldier proud to be part of this important occasion. When no one was looking he pushed one of the metal disks he’d just retrieved from downstairs—computerized detonators—into the explosive, pushed the button to arm it and fluffed up the moss, obscuring the device. He did the same to the arrangement in the back, which would detonate via a radio signal from the first detonator.

These two lovely arrangements were now lethal bombs, containing enough explosive to obliterate the entire room.

The tone in Rhyme’s lab was electric.

Everyone, except Pulaski, on a mission at Rhyme’s request, was staring at the criminalist, who was in turn gazing at the evidence charts that surrounded him like battalions of soldiers awaiting his orders.

“There’re still too many questions,” Sellitto said. “You know what’s going to happen if we push that button.”

Rhyme glanced at Amelia Sachs. “What do you think?” he asked.

Her ample lips tightened. “I don’t think we have any choice. I say yes.”

“Oh, man,” Sellitto said.

Rhyme said to the rumpled lieutenant, “Make the call.”

Lon Sellitto dialed a little-known number that connected him immediately to the scrambled phone sitting on the desk of the mayor of New York City.

Standing in the conference room in HUD, which was filling up with soldiers and their guests, Charles Hale felt his phone vibrate. He pulled it from his pocket and glanced down at the text message, another one from Charlotte Allerton. FAA grounding all flights. Trains stopped. Special team at NIST office checking U.S. clock. It’s a go. God bless.

Perfect, Charles thought. The police believed the complication about the Delphic Mechanism and his apparent plan to hack into the computer controlling the nation’s cesium clock.