Daniela marked them.

Rhyme: “I want to see the video again.”

The image came onto the screen once more. “Look at the wall, the stone. Is it a water reservoir?”

“It might be.” Ercole shrugged. “Carved stone. Stained with what might be water marks. And if converted, it could have had a doorway cut for access. There, that shadow suggests there is a doorway.”

Sachs said, “We’ve narrowed it to nine or ten locations. Can we do a search of them all? Get a hundred officers?”

Rossi seemed uncomfortable. “We do not have the resources I would like.” He explained that there’d just been reports of potential terror attacks in Italy and other parts of Europe recently and many officers had been pulled off non-terror crimes.

Rhyme had the video played once more: the stone, the noose, the unconscious victim, his chest rising slowly, the trickle of dust, the—

“Ah. Look at that.” His voice was a whisper. But everyone in the room turned to him immediately. He grimaced. “I saw it before but didn’t think a damn thing of it.”

“What, Rhyme?”

“The dust and pebbles, falling from the wall.”

Sachs and Ercole spoke simultaneously. She: “Subway!” He: “Rete Metropolitana!”

“A train’s shaking the walls. Ercole, quick, what lines run through the areas we’ve marked?”

He called up a subway system schematic on the laptop. Looking it over, Daniela drew the transit lines on their working map.

“There!” Rossi called. “That water reservoir, the small one.”

It was a room about twenty by twenty feet, at the end of an aqueduct. It was accessed by a passageway that ran to a street by a square on Viale Margherita.

Giacomo added, “I know that area. That reservoir would be in the basement of an old building, now abandoned. Prostitutes could have used the passages years ago, yes.”

“Abandoned,” Rhyme said. “So the doors might be sealed with the lock and chain the Composer cut through; that’s the rust and the slices of metal.”

“I’ll call the SCO,” Rossi said.

Daniela offered: “Servizio Centrale Operativo. Our SWAT force.”

Rossi spoke for several minutes, giving firm orders then hung up. “The central office is assembling a team.”

Sachs met Rhyme’s eyes. He nodded.

She asked, “How far away is that?” She stabbed the map, the entrance around which Daniela had drawn a red circle.

“No more than a few kilometers from us.”

“I’m going,” Sachs announced.

After a brief hesitation Rossi said, “Yes, certainly.” He looked to Giacomo and Daniela, and the three had a brief conversation in Italian.

Rossi translated, “Their vehicle is with other officers. Ercole, you drive Detective Sachs.”

“Me?”

“You.”

As they started for the door, Rhyme said, “Give her a weapon.”

“What?” Rossi asked.

“I don’t want her in the field without a weapon.”

“That’s irregular.”

We are not people who are well with irregularness…

“She’s an NYPD detective and a competitive shooter.”

Rossi considered the request. Then he said, “I am not aware of the agreement we have with the United States but I authorized gendarmes in pursuit of a criminal from France to enter Campania armed. I will do the same now.” He vanished and returned a few minutes later with a plastic pistol container. He jotted the number from the case onto a form and opened it. “This is a—”