First Sachs, then Sanchez pulled the grenade pins and pitched them inside.

A few seconds later, when they detonated, Sachs and her trio, followed by the south team charged forward, muzzles swiveling up and down out of one another’s way, as the tactical halogens affixed beneath the machine guns’ muzzles swept the dim place. “Police, police, police!”

The officers fanned out in the large room, which appeared unoccupied.

There were some storage areas and a bathroom. Officers cleared them fast.

She looked around. There was no doubt it was the Locksmith’s workshop. There had to be a hundred locks on the wall. Machinery too, and the key-making machine that she and Rhyme speculated he had. Books and papers. No computers, phones or tablets were visible, but they might be in drawers—or, she thought angrily, with him in a different location.

An apartment elsewhere, probably. There was a bed and a small kitchen but this didn’t seem a full-time residence.

“Breach successful,” she called into the radio. “Negative on suspects, main floor. Breaching cellar.”

In the floor was a trapdoor. As she’d thought before, it would be an unlikely escape route for him, but maybe he had found one of the old tunnels that latticed this part of town, to move goods underground from one company to another. None were shown on the city maps that she’d examined but they often weren’t.

The north team walked to the trapdoor. Sachs sighed. She hated clearing cellars.

“Away from the door. In case he rigged it.”

The officers stepped back. Sachs gripped the rope used to lift the door and, moving as far away as she could, yanked the heavy, three-foot square of wood up.

No explosions, no gunshots.

She and Sanchez stepped forward, staring down into the darkness, illuminated by their tactical halogens. She saw only disintegrating concrete and brick. “Police! If anyone’s down there, show yourself.”

Nothing appeared but leisurely dust motes.

“Camera.”

An ESU officer named Brill pulled from his belt the same model of camera that had been used in Whittaker’s apartment. He fed the lens through the trapdoor opening and clicked the unit to night vision. A three-hundred-and-sixty-degree scan showed trash bags and boxes, stacks of wood, a few pieces of rusting machinery whose purpose she couldn’t deduce.

“I count five instances of cover,” Brill said. “Boxes and the trash west and north and east corners. And the coal bin in the back.”

“Agreed.”

Brill substituted his camera for his machine gun.

Pulling another flash-bang off her tactical belt, Sachs said, “I’m going down.”

She glanced at Sanchez’s belt. The woman front slung then nodded and lifted off a grenade as well.

“Two each, quadrant them.”

If the Locksmith were below, he’d be hiding far away from the trapdoor. They’d fling the devices toward the corners of the cellar.

The woman nodded.

“One final chance. Show yourself!” When there was no response, Sachs tossed her first grenade then stepped back as Sanchez threw hers. As they were greeted with two loud cracks, they repeated the choreography, targeting the two remaining corners.

Sachs glanced down and drew her Glock, set her foot on the top rung of the stairs.

She stopped.

Jesus …

“Back, back!”

She clambered to the main floor, stumbling onto her side, and scrabbling away as a swirling cloud of flame shot from the opening and into the air, ten feet.