The Skin Collector (Lincoln Rhyme 11)

'How the store manager found the body. The flashlight. Our perp wanted to make sure we found the message from our sponsor.'

The words seemed a little flippant to Sachs but she'd always suspected that much of Rhyme's gruff facade and sardonic delivery were defense mechanisms. Still, she wondered if he raised the barricade of protection higher than he needed to.

She preferred to leave her heart unguarded.

'I'll collect it last,' Sachs told him. 'Every bit of light helps.'

She then walked the grid, which was Rhyme's phrase for searching a crime scene. The grid pattern was the most comprehensive approach in looking for evidence and assessing what had occurred. This technique involved walking slowly across the scene, then pivoting and moving one step to the right or left and returning to the far side. You did this over and over until you'd covered the entire space. Then you turned 90 degrees and covered the same ground again, perpendicular. Like mowing a lawn twice.

And with each step you paused to look up and down and side-to-side.

You smelled the scene too, though in this case Sachs couldn't detect more than Chloe's vomit. No methane or feces, which surprised her, considering that one of the pipes here was connected to the city's sewage system.

The search didn't reveal much. Whatever implements the perp had brought with him he'd taken - aside from the flashlight, cuffs and strips of duct tape. She did make one find, a small ball of crumpled paper, slightly yellowed.

'What's that, Sachs? I can't see very clearly.'

She explained.

'Leave it as is; we'll open it back here. Might have trace inside. Wonder if it's from her.'

Her. The Vic.

Chloe Moore.

'Or maybe from the perp, Rhyme,' Sachs added. 'I found what looked like fibers of newsprint or paper under her nails.'

'Ah, that could be good. Did they fight? Did she grab something of his? Or did he want something she had and rip it from her fingers - while she struggled to hold on to it? Questions, questions, questions.'

Using additional adhesive rollers and a small handheld vacuum, Sachs continued the search. Once these samples had been bagged and tagged she used a separate vacuum and a new roller to collect trace from places as far away as possible from where Chloe lay and where the unsub had walked. These were control samples - natural trace from this area. If analysis back at the lab revealed, for example, a clay-rich earth near one of the unsub's footprints, which didn't match any control specimens, they could conclude that he possibly lived or worked in or had some other connection to a locale loaded with clay. A small step toward finding the perp ... but a step nonetheless.

'I can't see many shoe or boot marks, Sachs.'

She was looking down at where he'd stood or walked. 'I can make a few out but they're not going to be much help. He wore booties.'

'Brother,' the criminalist muttered.

'I'll roll the footfalls for trace but there's no point in electrostaticking.'

She was referring to using sheets of plastic to lift shoe prints, in much the same way that fingerprints were lifted. The resulting tread pattern not only could suggest shoe size but might show up in the massive footwear database that Rhyme had created at the NYPD years ago, which was still maintained.

'And I'd say he had his own adhesive roller with him. It looks like he swept up as much as he could.'

'I hate smart perps.'

No, he didn't, Sachs reflected. He hated stupid perps. Smart bad guys were challenging and a lot more fun. Sachs was smiling beneath her N95 respirator. 'I'm going silent, Rhyme. Checking the entrance and exit routes. The manhole.'

She withdrew her Maglite, flicked on the powerful beam and continued down the tunnel toward the ladder leading up to the manhole, noting not a bit of pain from the persistent arthritis that had plagued her for decades; recent surgery had worked its magic. Her shadow, cast by the halogen spot behind, stretched out before her, a distorted silhouette of a puppet. The ground beneath the manhole was damp. This strongly suggested it was how he'd gotten into and out of the tunnel. She noted this fact then continued on, into the darker reaches beyond.

With every step she grew more uneasy. Not because of claustrophobia this time - the tunnel was unpleasant but spacious compared with the entrance shaft. No, her discomfort was because she'd seen the perp's handiwork - the tattoo, the cutting, the poison. The combination of his cleverness, his calculation and his perverse choice of weaponry all conspired to suggest that he'd be more than happy to hang around and try to stop his pursuers.

The flashlight in her left hand, while her right hovered near the Glock, Sachs continued down the increasingly dark tunnel, listening for footsteps, an attacker's breaths, the click and snap of weapons chambering rounds or going off safety or cocking.

None of those, though she did hear a hum from one or more of the conduits or the yellow IFON boxes, whatever they were. A faint rush from the water pipe.

Then a scrape, a flash of movement.

Glock out, left hand gripping the Maglite, forearm supporting her shooting hand. The muzzle followed the beam. Sweeping, scanning.