Mold, must, rot, the nose-tweaking snap of decaying paper. Air so heavy with dust it felt granular.

Milo opened the ancient Venetian blinds. Where light penetrated the apartment it highlighted the particulate storms that we set off as we moved through tight, shadowed spaces.

Tight because virtually the entire front of the flat was filled with bookshelves. Plywood cases, separated by narrow aisles. Unfinished wood, warped shelves suffering under the weight of scholarship.

Life of the mind. Eldon Mate had turned his entire domicile into a library.

Even the kitchen counters were piled high with books. Inside the fridge were bottles of water, a moldering slab of hoop cheese, a few softening vegetables.

I walked around reading titles as dust settled on my shoulders. Chemistry, physics, mathematics, biology, toxicology. Two entire cases of pathology, forensics, another wall of law-civil liability, jurisprudence, the criminal codes of what appeared to be every state of the union.

Mostly crumbling paperbacks and cold shabby texts with torn spines and flaking pages, the kind of treasures that can be found at any thrift shop.

No fiction.

I moved to the tiny back room where Mate had slept. Ten feet square, low-ceilinged, lit by a bare bulb screwed to a white porcelain ceiling fixture. Bare gray walls jaundiced by western light seeping through parchment-colored window shades. The cheap cot and nightstand took up most of the space, leaving barely enough room for a raw-looking three-drawer pine dresser. Ten-inch Zenith TV atop the dresser-as if Mate had had to make up for Mrs. Krohnfeld's video excess.

A door led to the adjoining bathroom, and I went in there because bathrooms can sometimes tell you more about a person than any other space. This one didn't. Razor, shaving cream, laxatives, antigas tablets, and aspirin in the medicine cabinet. Amber ring around the tub. Bar of green soap bottomed by slime, sitting like a dead frog in a brown plastic dish.

The closet was skinny and crammed full, sharp with the reek of camphor. A dozen wash-and-wear white shirts, half that many pairs of gray twill slacks, all Sears label; one heavy charcoal suit from Zachary All, wide lapels testifying to a long-ago fashion cycle; three pairs of black cap-toe oxfords stretched by cedar shoe trees; two beige windbreakers, also Sears; a pair of narrow black ties hanging from a hook-polyester, made in Korea.

"What was his financial situation?" I said. "Doesn't look like he spent much on clothes."

"He spent on food, gas, car repairs, books, phone and utilities. I haven't gotten his tax forms yet, but there were some bankbooks in there." Indicating the dresser. "His basic income seems to have been his U.S. Public Health Service pension. Two and a half grand a month deposited directly into the savings account, plus occasional cash payments, two hundred to a thou each, irregularly spaced. Those I figure were donations. They add up to another fifteen a year."

"Donations from who?"

"My guess would be satisfied travelers-or those who survived them. None of the families we've talked to admit paying Mate a dime, but they'd want to avoid looking like they hired someone to kill Grandma, wouldn't they? So he was pulling in around fifty grand a year, and in terms of assets he was no pauper. The three other passbooks were for jumbo CDs of a hundred grand each. Dinky interest, doesn't look as if he cared about investing. I figure three hundred would be about a decade of income minus expenses and taxes. Looks like he's just about held on to every penny he's earned since going into the death business."

"Three hundred thousand," I said. "An MD in practice could put away a lot more than that over ten years. So he wasn't in the travel business to get rich. Notoriety was the prize, or he really was operating idealistically. Or both."

"You could say the same for Mengele." Flipping the skimpy mattress, he peered underneath. "Not that I haven't done this already." His back must have twinged, because he sucked in breath as he straightened.

"Okay?" he said.

Suddenly the room felt oppressive. Some of the book aroma had made its way in here, along with a riper smell, more human-male. That and the mothballs added up to the sad, sedate aroma of old man. As if nothing here was expected to ever change. That same sense of staleness and stasis that I'd experienced up on Mulholland. I was probably getting overimaginative.

"Anything interesting on his phone bills?" I said.

"Nope. Despite his publicity-seeking, once he got home, he wasn't Mr. Chatty. There were days at a time when he never phoned anyone. The few calls we did find were to Haiselden, Zoghbie, and boring stuff: local market, Thrifty Drugs, couple of used-book stores, shoemaker, Sears, hardware store."

"No cell phone account?"

He laughed. "The TV's black-and-white. Guy didn't own a computer or a stereo. We're talking manual typewriter-I found blank sheets of carbon paper in the dresser."

"No sheets with any impressions for a hot clue? Like in the movies?"

"Yeah, right. And I'm Dirty Harry."

"Old-fashioned guy," I said, "but he pushed the envelope ethically."

I opened the top drawer of the dresser on mounds of folded underwear, white and rounded like giant marsh-mallows. Stuffed on each side were cylinders of rolled black socks. The middle drawer contained stacks of cardigans, all brown and gray. I ran my hand below them, came up empty. The next drawer was full of medical books.

He said, "Same with the bottom. Guess next to killing people, reading was his favorite thing."

I crouched and opened the lowest drawer. Four hardbacks, the first three with warped bindings and foxed edges. I inspected one. Principles of Surgery.

"Copyright 1934," I said.

"Maybe if he'd kept up, that liver would've fared better."

The fourth book caught my eye. Smaller than the others. Ruby-red leather binding. Shiny new… gold-tooled decorations on the ribbed spine. Ornate gilt lettering, but a crude, orange-peel texture to the leather- leatherette.

Collector's edition of Beowulf published by some outfit called the Literary Gem Society.

I picked it up. It rattled. Too light to be a book. I lifted the cover. No pages within, just hollow, Masonite space. MADE IN TAIWAN label affixed to the underside of the lid.

A box. Novelty-shop gag. Inside, the source of the rattle:

Miniature stethoscope. Child-size. Pink plastic tubing, silvered plastic earpieces and disc. Broken earpieces- snapped off cleanly. Silvery grit in the box.

Milo's eyes slitted. "Why don't you put that down."

I complied. "What's wrong?"

"I checked that damn drawer the first time I tossed the place and that wasn't in there. The other books were, but not that. I remember reading each of the copyrights, thinking Mate was relying on antiques."

He stared into the red box.

"A visitor?" I said. "Our van-boy commemorating what he'd done? Broken stethoscope delivering a message? 'Mate's out of business, I'm the doctor now'?"

He bent, wincing again. "Looks like someone clipped the plastic clean. From the dust, maybe he did it right here…very clean."

"No problem if you had bone shears. One very nasty little elf."

He rubbed his face. "He came back to celebrate?"

"And to leave his mark."

He walked to the door, looked out at the bookcases in the front room, scowled. "I've been here twice since the murder and nothing else looks messed with…"

Talking to himself more than to me. Knowing full well that with thousands of volumes, there was no way to be sure. Knowing the yellow tape across the door was meaningless, anyone could've pried the lock.

I said, "The bum Mrs. Krohnfeld saw-"

"The bum walked up the stairs in plain sight and ran away when Mrs. Krohnfeld screamed at him. She said he was a mess. Wouldn't you expect our boy to be a little better organized?"