Two Sundays ago, on a slow afternoon in the flat industrial town of South San Francisco, officer Paul Ziemer sat down in a police station interrogation room with a nervous, bearded man who had identified himself as Mr. Stapley.

"I'm really dry," the man told Ziemer. "Can I have a drink of water?"

Ziemer took Stapley across the hall and watched from behind as he took a drink from the water fountain. Stapley had not been charged with anything, but Ziemer could see that there was trouble here: the picture on his driver's license looked like someone else, and a search of his car had turned up a silencer and a .22-cal. automatic -- a weapon, Ziemer said later, "commonly used as an assassin gun."

His drink finished, the man told Ziemer his name was Leonard Lake. His breathing deepened, and his eyes started to roll. He told Ziemer he was wanted on felony charges in Mendocino County. Then he began gasping, and by the time Ziemer had rushed to call the paramedics Lake had slumped to the floor -- the apparent victim of some fatal poison pill he had managed to slip into his mouth.

This week, on two wooded acres here in the Sierra foothills, grim police investigators are digging up what Lake, allegedly with a companion still at large, may have left behind. Using backhoes and shovels to turn over the dry earth, police have filled at least three bags with what appear to be fragments of buried human bones.

Skeletal remains of two bodies, neither positively identified, have been unearthed just outside what police describe as a concrete bunker used for some form of bondage.

With evidence that perhaps as many as 20 people connected to Lake and his companion may be missing, police at Lake's mountain retreat have found photographs of clothed and unclothed women, videotapes of women being threatened with death, vials of chemicals, a diary discussing domination of women and piles of what a deputy described as "Frederick's of Hollywood-style clothing -- we're talking lingerie."

"Fingernails, teeth, bones, skulls, fragments, whatever -- in little tiny pieces," Calaveras County Sheriff Claud Ballard said Tuesday as he listed some of the week's yield for reporters clustered outside Lake's property. "I've been in this business 27 years. I've seen a lot of terrible things. But I've never run into anything like this."

A nationwide manhunt is under way for Charles C. Ng, the 24-year-old ex-Marine who police say appears on one of the videotapes, in which he is allegedly seen slashing a woman's clothing with a knife. A San Francisco police spokesman said that the FBI had issued a warrant charging Ng with unlawful flight to avoid prosecution and that dozens of people had called a new, 24-hour telephone-tip line to report having spotted Ng.

An Asian man believed by police to be Ng, a convicted thief released a year ago from Leavenworth, brought Lake to the attention of police this month. Ziemer and another South San Francisco officer responded two Sundays ago to a report that an Asian male had stolen a $75 vise grip from a lumberyard and had dropped it into the trunk of a tan Honda as he fled.

Police said that the car was Lake's, and that Lake emerged from the lumberyard and offered to pay for the tool. But an inspection of the trunk turned up the gun and silencer, police said, and the Honda was registered to Paul Cosner, a San Francisco auto broker who disappeared last November after telling a friend that he had to deliver a car to a customer.

As Lake lay in a hospital where he died without regaining consciousness, the auto records led police to the property Lake had bought three years ago in this county of dry hills and restored gold-mining towns. Inside Lake's small house, a San Francisco investigator identified a videotape machine as one belonging to Harvey and Deborah Dubs, a San Francisco couple who disappeared last summer with their 16-month-old son.

Within two days, police began digging up what a sheriff's deputy said appear to be four "burn sites" that may include bone fragments. They found at least two videotapes whose contents have not been made public but which they say show Lake and Ng verbally brutalizing women.

They also examined the diary, which Ballard said is a day-to-day account of a man discussing his belief that the ideal woman submitted to men in every way. "I think the man was very insecure, about as insecure a person as I've ever come across in my life," Ballard said.

"The perfect woman for me is one who is totally controlled, a woman who does exactly what she is told and nothing else," Lake wrote in the diary, according to newspaper accounts. "There is no sexual problems with a submissive woman. There are no frustrations, only pleasure and contentment."

Lake's compound, now scarred and flagged like a forest archeological site, includes a small concrete structure that increasingly excited media reports have referred to as a "torture chamber" and a "sinister chamber of sex and death." Sheriff's deputies said one tiny room inside, windowless and accessible only by a double-locked door, contained a small makeshift bed, some women's makeup and a small plastic bucket apparently used as a chamber pot.

No obvious torture devices have been found at the compound, deputies said, and the photographs showed nude, clothed and partially clothed women who were smiling and did not appear to be under restraints.

The portrait of Lake that has emerged over the last two weeks describes a Vietnam veteran who was arrested two years ago in connection with a cache of illegal guns in Mendocino County and imagined himself something of a backwoods survivalist. According to Marine records of his Vietnam tours, he was a radar technician unlikely to have been in combat, but published reports say that Lake talked about violence he had seen and joined.

"He kind of figured that -- what's the old saying -- 'tooth for a tooth and eye for an eye,' " said Jim Southern, a neighbor who knew Lake as Charles Gunnar and invited Lake to weekly Bible study classes in his home over the last year or so. Police say the real Gunnar, a friend of Lake's, was reported missing.

Southern said Lake, serious and quiet, would sit on the couch with his Bible and join group discussions enthusiastically. He told Southern that the Mormon church appealed to him more than any other but that he preferred to worship outdoors.

On one occasion, Southern said, Lake had brought up an Old Testament passage in which God gave strength to soldiers preparing to kill in battle. "He said, 'What's the difference?' ?" Southern said. " 'He sanctioned it back then. Why shouldn't He sanction it now.' "

Like the rest of Wilseyville, Southern is growing accustomed to the telephone calls and to reporters flocking up his dirt driveway. In the main hotel in San Andreas, a harried clerk fends off reporters clamoring for a long-distance line. The sheriff, whose appearances are few and reluctant, seems overwhelmed by camera crews competing for first shots of the unearthed graves.

"He was kind of strange," said Karren Howsmon, a neighbor who also knew Lake as Gunnar, "but he was always pretty polite, and we never dreamed anything like that was going on."