Earlier, from her elevated perch, she had spotted five oval excavation areas. She'd inspected three. Alert for signs of returning diners, she hurried toward the fourth. She never got there. Halfway between the third and fourth was a bear dig of a very different aspect. It was linear, the rocks turned over in neat rows and not as deep, six to eight inches at most.

Things natural tended to eschew straight lines. Lines were a mathematical construct taught to the disordered minds of children until, in adulthood, people favored them, writing, digging, planting and, when possible, walking in them.

On hands and knees, Anna crawled along the linear upset of talus. Rocks had not been dug per se, but pried loose and overturned. On closer inspection she could see marks in the stone; not the evenly spaced scrape of claws but sharp, angular scratches that had to have been made with a shovel or Pulaski. A person, most probably the person Anna sought, had been to the cirque for the same reason as the bears: to dig up army cutworm moths.

Sitting on her heels, eyes roaming the edges of the depression for interlopers of any species, she thought about the strange young man, Geoffrey Mickleson-Nicholson. The day they'd seen him, before the grizzly had come to their camp, they had passed a field of glacier lilies, another preferred food of the Glacier bear population. Someone with a spade had been digging them up. Most likely the obvious choice: Geoffrey Whoever. At the time it seemed of little importance. Illegal certainly, but one man with a shovel and a backpack was not going to dig the lilies to extinction.

There was nothing to indicate the digger of moths was the same person as the digger of lilies except that people pilfering the natural food of bears was an oddity. Rare to catch one doing it; statistically improbable to find two. The young man with the lovely smile and the suspicious habits was not a bear researcher; Joan would have known him. At least he wasn't a bear researcher in Glacier.

Could an adolescent rogue researcher be murderously messing about with Glacier's grizzlies? The concept was absurd but Anna didn't throw it out entirely. She merely consigned it to the heap in her brain where other absurdities connected with this case lay.

Because it was cold and she was tired and the sun was going to be down in a couple of hours, she thought of werewolves. As a rational westerner, Anna didn't believe in the existence of the mythical monsters. As the sister of an eminent psychiatrist, she knew there were nutcases wandering the moonlit streets who sincerely believed they were werewolves. People suffering from lycanthropy. On rare but recorded occasions these individuals lived out their psychosis to the point of killing, ripping out throats and drinking blood as they believed they must in their wolf-like state. Was it possible a person could believe himself a grizzly? Why not? People believed they were Napoleon, the Virgin Mary, the reincarnation of Michelangelo. In Mississippi, Anna'd dealt with a woman who believed herself to be the mother of eight children, all penguins.

Why not a bear?

Like those suffering from lycanthropy, could the psychosis go so far as to drive the sufferer to seek to live as a bear would live, eat as a bear would eat and kill as a bear would kill?

Anna thought back on the night she and Joan had been visited. Neither of them had seen an animal, merely heard what they believed to be an animal. They had only Rory's word for it that there'd been a bear and Rory was not exactly the poster boy for mental stability.

A deep and rotten core of fear opened in Anna, making her nauseated. She and Buck had been siphoned off to assist Ruick. Joan was alone in an isolated camp with Rory Van Slyke, an excellent candidate for the Bear Boy.

"Wait, wait, wait," Anna said, calming herself. Rory could have done many things but he couldn't have come to the cirque with a navy stuff bag, and it had not been he who had been digging lilies. The altitude, the solitude, a long day's work were scrambling her thoughts.

Creating a trance-like state induced by self-hypnosis that allows the fears and wish-images of the subconscious mind to be accessed by the conscious mind. Anna'd heard Molly say that in a lecture at Yale once ten years before. Then, she'd thought it a wonderfully phrased crock of shit. Now she wasn't so sure.

"Werebears," she said out loud to mock herself out of the heebie-jeebies.

It didn't work. The missing flesh so carefully cut from the face of Mrs. Van Slyke-a person using a knife rather than teeth and claws to pull the edible flesh from the prey? An absorbing if macabre theory. Much that was known didn't fit with the werebear tale: the specificity and tidiness of the flesh removal, caching the flesh, stealing film, moving and hiding the body.

Anna put it from her mind and concentrated on trying to track the individual with the shovel. Shovel: that was a reassuring indicator of sanity. A person so far gone with mental illness as to imagine himself a bear by night would surely dig with his hands.

Six o'clock; time was up but Anna was not finished.

Clearing her mind of everything that was not visible on the ground, she slid easily into the tracker's zone, a quiet place where one could wait for as long as need be for the minutest sign to come clear. The shovel dig was fresh, not more than twenty-four hours old.

The fine layer of silt on the bottoms of the overturned stones was dry on the surface but, when scratched, still retained vestiges of moisture beneath. Overturning the stones carefully, she saw that the moths licked up by real bears had here been scraped off by human hands. The trail the fingers left during the harvest was clear. The navy bag had told Anna the gatherer of moths had visited this site. Had he used the bag to store his moths to cat later? Did he cat the moths, as the bears did, al fresco, one rockful at a time?

There was no way to tell which end of the linear dig was the beginning and which was the end. Anna stood a moment choosing the most logical direction from which the digger might have come. The same way she had, south from Highline Trail. She began with the opposite end of the line of disturbed talus, the end from which he had most likely departed. Squatting on her heels, she focused loosely on the ground and waited.

The low angle of the sun was perfect for tracking. And besides herself and bears, the digger was probably the only human who'd walked here for maybe years. Had conditions been otherwise she would not have been able to track over such an inhospitable surface.

A tread mark in the dust half obliterated by what must be the print from an enormous padded paw. A scuff, straight and smooth that could be made only by the side of a shoe- leather or rubber. Four yards farther on a veritable signpost: a single slab of talus overturned by the edged tool. Why that one, Anna couldn't guess. It must have looked particularly mothy to the guy.

A puffing, like a small steam engine straining uphill, broke her concentration. Before she looked she knew what it was. She'd heard it the night of the bear visitation. Fear, sudden, new, remembered, washed down from throat to belly to bowels.

The bears had come to feed.