The crime lab - officially known as the Forensic Science Center, but never called that - was a massive building that had once been a schoolhouse, located just a few blocks from the Roundhouse at Eighth and Poplar Streets.

    The reigning sovereign of the documents section was Sergeant Helmut Rohmer. Hell Rohmer was thirty-five, and a giant, measuring six-four, weighing two-fifty. Besides his strange and eclectic taste in music, which ran from Iron Maiden to Kitty Wells, he was known for his T-shirts - always black, never bearing the same saying twice. He must have had hundreds. He was starting to receive them in the mail, even from people he had helped put away in prison. Today his shirt read:

    His considerable arms were ringed with rose tattoos, or some variation, which now finished with ivy circling his wrists and ending on the backs of his hands. He was always well-groomed - right down to his oddly manicured fingers. Jessica figured that his manicures had something to do with his sense of the tactile. Hell Rohmer didn't want anything interfering with his sense of touch. He was almost metaphysical in his approach to document forensics. It was one of the reasons why he and Byrne spoke the same language.

    'Good evening, sleuths,' Hell said.

    'Good evening, alchemist,' Byrne replied.

    Hell smiled. 'I have your paper,' he said. 'You can only hide from the Weavemeister for so long.'

    On the wall were six enlarged photographs of the paper found on the victims, front and back. The photographs showed the blood that had leached from the lacerations on each of the victim's foreheads, as well as the small dot of blood from the shallow puncture wound. A line, a dot, and the rough figure eight where the ears were mutilated.

    'What do we have?' Jessica asked.

    Hell picked up a small square of the paper sample, cut from the end of one of the bands. 'This is pricey stuff,' he said, running a finger across the slightly pebbled surface. 'It's beautiful, really. Our boy has exquisite taste.' Hell zoned for a moment, his eyes going a bit unfocused. Hell Rohmer was definitely a touchy-feely sort of guy.

    'Hell?'

    'Okay. Sorry. The paper is handmade, a hundred percent cotton, acid-free. Which puts it into the same category as about ten thousand brands. I'm not equipped to do a comparison test to determine the make, and I was just about to send it off to the FBI - which, as you know, can take a month or two to get back - when I saw something.' Helmut held up a sample. 'This was cut from the paper we took from the female victim. If you look here, you can see a small segment of a watermark.' Hell held the paper up to a strong light, but not too close. Jessica saw what looked like the portion of a shoulder.

    'Is that a cherub of some sort?' Jessica asked.

    Hell shook his head. 'The watermark is Venus de Milo. It's not on the other sample, so I'm thinking these were cut from a larger sheet.'

    Hell displayed another printout. It was an extreme close-up of the edge of the paper, photographed through a microscope. 'This was cut with a large blade, which is indicated by the slight tearing of the fiber. I think he used a paper cutter, instead of an X-acto blade, scissors, or razor blade. The shearing is consistent front to back, with the fibers pushed downward. Too uniform to have been done by hand.'

    Hell pointed to the sample.

    'And while this might look white, it is really Felt Light Grey. Deckled on two sides, which leads me to believe it's deckled on four. The band is twenty-four inches long, which leads me to believe it was cut from a sheet that was twenty-four by twenty-six, which is fairly standard in printmaking.'

    'This is printmaking paper?'

    'Among other things.'

    Hell put the sample down, picked up a few pages of computer printouts.

    'It's the watermark that jumped out. Without it, we would have had to wait for Washington on this.' He pointed to one of the lines on the printout, highlighted in lime green. 'The manufacturer of this paper is headquartered in Milan, Italy, and the line is called Atriana. Really high-end stuff. Printmaking, mostly, but they make all kinds of multi-use paper - stationery, canvas, vellum, linen. But this stuff is top of the line. One sheet of this paper retails for about seventy dollars.'

    'Wow'

    'Yeah,' Hell said. 'And dig this. This company also supplies the paper for the Euro.'

    'The currency?'

    'The one.'

    'They have two distributors in the US,' Hell said. 'As far as I can tell this paper is available at only twenty retail stores across the country. Mostly art supplies and specialty paper shops. Unfortunately - for us, not our bad boy - the paper can be ordered from a dozen online retailers.'

    'Are there any stores in Philly that carry it?' Jessica asked.

    'No,' Hell said. He smiled, held up a 3 x 5 card with an address on it. 'But there is a store in Doylestown.'

    Jessica took the address.

    'No applause?'

    Jessica clapped.

    'Thank you. And now to the wax.' On the table sat a small covered glass dish. The wax seal was inside. 'This is standard candle wax, not sealing wax, which is why it has begun to disintegrate.'

    'What's the difference?'

    'Well, about five hundred years ago, sealing wax was made primarily of beeswax and something called Venice turpentine, which is an extract of the larch tree. The wax was uncolored in those days, but when the Renaissance hit, folks started to color it with vermilion, and do you really want to know any of this?'

    'Maybe one of these days,' Jessica said. 'Right now I'd love to know where our boy bought this. I would like a clear video of him leaving the store, and a copy of his driver's license. Do you have that?'

    'No. And what's worse, this candle wax is available at every Rite- Aid, Wal-Mart and Target in the country. But not in this color.'

    'What do you mean?'

    'Well, what I was getting to, before I was so brusquely interrupted, was that this particular sample was not colored with any old vermilion.'

    It took Jessica a second to realize what Hell Rohmer was saying. One look at Byrne told her he'd gotten it as well. She turned back to Hell.

    'No.'

    'I'm afraid so. The coloring is blood. This is a bad, bad pony, this guy.'

    Jessica looked at Byrne just as someone entered the lab and stopped by the door. Hell crossed the room, disappeared from Jessica's line of sight. In the reflection from one of the glass cabinets she saw that the new arrival was Irina Kohl. Irina had with her a few folders, one of which she placed in Hell's hands. Then Jessica saw the diminutive Irina get on her tiptoes and kiss Hell Rohmer flush on the mouth. Hell turned and saw that Jessica could see them in the cabinet's reflection.

    The two of them, now red as raspberries, walked back to join Jessica and Byrne.

    'Urn, you didn't see that,' Hell whispered to Jessica.

    'See what?'

    Hell winked.

    'I'm glad you're here,' Irina said, plowing forward. 'I think we may have something on the murder weapon.'

    Irina Kohl worked in the lab's firearms ID unit, which also handled tool marks, and was in her late twenties, a prototypical lab dweller - neat in appearance, precise in manner and speech, probably a little too smart for Mensa. Beneath her lab coat she wore a suit coat, white button-down shirt, and lavender knit tie.

    Irina opened a folder, removed some enlargements.

    'The wire used as the ligature was made of woven multi-strand titanium.' She pointed to an extreme close-up of the ligature marks on the first two victims. Even to the naked eye the woven characteristics were visible. The flesh bore an imprint of the three-strand weave. 'We found traces of the metal in the wound.'

    'What is something like this used for?' Jessica asked.

    'There are a lot of uses for it. In general, titanium wire is specified for medical devices, bone screws, orthodontic appliances. In different gauges it is all over the aerospace, medical and marine manufacturing map. It is low-density and has a high resistance to corrosion.'

    Irina then picked up a blown-up photograph, as well as a pair of slides.

    'I also found hair samples in the ligature wound on the first two victims. We haven't gotten a crack at the third victim yet.' She pointed to the two slides. 'These are from Sharon Beckman and Kenneth Beckman.'

    'Do you think this is our killer's hair?' Jessica asked.

    'No,' Irina said. 'I'm afraid not. These samples are definitely not human.'

    Jessica looked at Byrne, back. 'Not human as in ...'

    'Well, animal.' Irina pushed up her thick glasses. She scrunched her face, as if smelling something unpleasant. Jessica supposed this was her way of waiting for the conversation to regenerate. She also noted that the woman was wearing two different lipsticks. One shade on her upper lip, one on the lower.

    'Well, duh, Jess,' Jessica said, berating herself. 'I mean, what else, alien?'

    Irina continued, undaunted. 'Domestic animal specifically.'

    'We're talking dog or cat?' Jessica asked.

    'Not domesticated, necessarily. What I mean is domestic as in cow, sheep, horse.' Irina got a little more animated. 'See, if we're talking the hair of domestic animals there are a number of variations in color and length. However, a lot of these identifiers are pretty general. In order to tell the difference between, say, a dog and a cat, or between a cow and a moose, you really need the root to be present. Which, unfortunately, in this case, we do not have.'

    She slipped a slide onto the stage of a microscope, clipped it in.

    'But we're just getting started.' Irina smiled at Hell. Hell beamed.

    Irina then peered into the microscope eyepiece, did a little fine focusing. 'If you take a look here, you can see it.' She stepped back.

    Jessica stepped forward, looked through the microscope.

    'You see it is quite coarse. The medulla is unbroken,' Irina said. 'The pigment is fine and evenly distributed.'

    'Yeah,' Jessica said. 'I was just going to say that about the medulla.' The image she saw looked like a long dark brown tube. She might just as well have been looking at a Tootsie Roll. Hell Rohmer watched Irina, sunny with admiration, seething with forensic lust. Jessica and Byrne had worked with the two of them many times. Hell and Irina liked to have scientifically clueless detectives and other investigators look though microscopes. It validated them as criminalists.

    'What tipped me was the ovoid structures,' Irina added.

    'Every time,' Jessica said, stepping away from the microscope. 'So what are you saying? I mean, I understand it. Tell us for Kevin's benefit.'

    Byrne smiled.

    'Well, this is not exactly my field,' Irina said. 'So I'm going to send this out. We should know something by tomorrow at the latest.'

    Jessica handed Irina a card with her cellphone number on it. 'Call me the second you have it.'

    'Will do,' Irina said. 'And our freaky killer better get some game.'

    'Why's that?'

    Irina smiled. Jessica saw her hand covertly brush up against Hell Rohmer's hand. 'We're about to make his life awfully uncomfortable.'

    As a rule, criminals have no idea who the people are who plug away in forensic labs all over the world and how dedicated they are to rooting out the truth. If they did know, they wouldn't be so cavalier about leaving at their crime scenes any one of the million skin cells or hundreds of hairs we shed every day, not to mention saliva, footprints, blood, or fibers from clothing.

    As Jessica got into the car she also thought about how her job sometimes resembled an episode of The X-Files.

    These samples are definitely not human.