The frown vanished and she turned to her right and called, "Ron! Clear!"
Footsteps from around the corner. Rhyme watched Pulaski approach, also holstering his weapon. "Lincoln!" A curious glance at the lawyer.
Rhyme introduced them.
Pulaski blurted to Rhyme, "What're you doing here?"
"Just asking the same question, Rookie."
And the answer was soon clear, once he and Sachs explained what had brought them to the building on Ridge Street in lower Manhattan, on their respective missions. The victim of the unsub whom Sachs had been on the trail of for the past several weeks, Todd Williams, was in fact the man who'd posted the blog about the dangers of DataWise5000 controllers. Since Rhyme was no longer doing criminal work she'd never had reason to mention Williams's name.
Sachs explained that she and Pulaski had run down a lead: The unsub had taken a car service from Queens to this area and the driver had seen him go through the back door of this building about four hours before Williams's death.
Rhyme said, "Williams published a blog piece about the risks of a particular kind of Wi-Fi smart controller--the same type that we think malfunctioned in the escalator and probably caused the access panel to open. Since the widow can't sue the escalator manufacturer--they're in bankruptcy--we're considering a suit against the controller company. We were hoping Williams could be an expert witness, or at least tell us more about how the controllers could fail. But now..."
Sachs asked, "You thinking what I am?"
"Yep. Your unsub reads Todd's blog about the controller, thinks it might be a nifty murder weapon--for whatever reason. Contacts Todd, arranges to meet him here. Learns what he needs to so he can hack into the controller."
Sachs continued the likely narrative: "Then suggests they go to the club, Forty Degrees North. But before they get there, he pulls Todd into the construction site and beats him to death with his hammer. Makes it look like a robbery. He killed him there, rather than here, to keep the investigation focused away from Williams's office."
Whitmore said, "I don't quite follow this, Mr. Rhyme."
Rhyme said, "Amelia was after the perp at the mall in Brooklyn. She assumed it was a coincidence that the escalator collapsed while she was there."
Sachs added, "But it wasn't. Looks like Unsub Forty knew how to hack the controller and opened the door intentionally."
"To cause a distraction and escape?" Pulaski asked. "When he saw you were after him?"
Rhyme's face tightened at the young man's flawed thinking. "How would he know there was a DataWise controller in the escalator?"
Blushing, the young man said, "Sure, sure. Wasn't thinking. He'd have had it planned out ahead of time. He was at the mall--to kill either somebody at random or Frommer in particular--by popping open the access panel."
Pulaski's Motorola crackled. He stepped aside to take the transmission.
Sachs explained to Rhyme and Whitmore, "The unsub was spotted here about twenty minutes ago. We called in backup. That's why the weapons; we thought you might be him when we heard you on the other side of the building."
The young officer rejoined them. "One car patrolling the neighborhood, other's pulling up here. No sign of him yet."
Rhyme said, "Any chance he's in the building?"
"Homeless guy said he was standing at that intersection," Sachs said, nodding. "He probably would have seen him if the unsub'd come this way."
Whitmore asked, "But I'm curious. Why would he come back here?"
Rhyme said, "He might live nearby." The area was mostly commercial but there were pockets of tenements and newer--that is, seventy-five- or eighty-year-old--apartments.
"Or he's worried he didn't cover his tracks well enough and came back to look for evidence. He saw us and took off." She looked over the building. "See if it's been broken into, Ron."
He circled the structure and returned. "Windows're intact. But the back door might've been jimmied. Scratch marks."
Rhyme couldn't feel the thud in his insensate chest but he knew this occurred... from the rapid pulse in his forehead. "You said to look for evidence, Sachs. He could also--"
"Have come here to destroy it!" She spun toward the building.
It was at just that moment that there came a muffled whump from within the building. Whatever kind of incendiary device Unsub 40 had planted, it must have been quite large. Within seconds, smoke and flames began spiraling out of the ground-floor windows, which had shattered from the heat.
Rhyme caught a mouthful of smoke and ash and, coughing hard, he struggled to maneuver backward in his chair. Evers Whitmore helped him do so, kicking away a trash basket that was blocking the criminalist's escape. Ron Pulaski called Dispatch to send the FDNY.