"A tiger?" Jamilla was the one to express the disbelief we were all feeling. "Are you sure? That doesn't seem possible, Dr. Pang."

"Allen," Walter Lee said, "explain, please."

"Well, as you know, humans are heterodonts; that is, they have teeth of different sizes and shapes, which serve different functions. Most important would be our canines, which are situated between the lateral incisor and the first premolar on each side of each jaw. The canines are used to tear food."

Walter Lee nodded, and Dr. Pang continued. He was speaking solely to the M.E. at this point. I caught Jamilla's eye, and she gave me a wink. I liked that she had a sense of humor.

Dr. Pang seemed to be in his own world. "In contrast to humans, some animals are homodents. Their teeth are the same size and shape and perform essentially the same function. This is nottrue of large cats, however, especially tigers. The teeth of tigers have been adapted for their feeding habits. Each jaw contains six pointed cutting teeth, two very sharp, recurved canines, and molars that have evolved into cutting blades."

"Is that important in terms of these murders?" Jamilla Hughes asked Dr. Pang. I had a version of the same question.

The smallish man nodded enthusiastically. "Oh, of course. Certainly. The jaw of a tiger is extremely strong, able to clamp down hard enough to crush bone. The jaw can only move up and down, not side to side. This means the tiger can only tear and crush food, not chew or gnaw." He demonstrated with his own teeth and jaw.

I swallowed hard, and found my head shaking back and forth. A tiger was involved in these murders? How could that possibly be?

Dr. Pang stopped talking. He reached up and scratched his bald pate rather vigorously. Then he said, "What completely baffles me is that someone commanded the tiger away from its prey after it struck — and the tiger obeyed. If that hadn't happened, the prey would have been eaten."

"Absolutely amazing," the medical examiner said, and gave Dr. Pang a pat on the back. Then he looked at Jamilla and me. "What's the saying — 'Catch a tiger, if you can?' A tiger shouldn't be all that hard to find in San Francisco."

The large white male tiger was making a chuffing sound, a muted, backward whistle. The sucking noise came from deep inside its wide throat. The sound was almost unearthly. Birds took flight from a nearby cypress. Small animals scampered away as fast as they could.

The tiger was eight feet long, muscular, and weighed just over five hundred and eighty pounds. Under ordinary circumstances its prey would have been pigs and piglets, deer, antelope, water buffalo. There were no ordinary circumstances in California. There were lots of humans, though.

The cat pounced quickly, its lithe, powerful body moving effortlessly. The young blond man didn't even try to resist.

The tiger's massive jaws opened wide, then clamped down onto the man's head. The cat's jaws were strong enough to pulverize bone.

The man screamed, "Stop! Stop! Stop!"

Amazingly, the tiger stopped.

Just like that. On verbal command.

"You win." The blond man laughed and patted the tiger, which released his head.

The man then twisted sharply to the left. His movements were almost as quick and effortless as the cat's. Now the young man pounced. He attacked the tiger's vulnerable creamy white underside, grabbing onto flesh with his teeth. "Got you, you big baby! You lose. You're still my love slave."

William Alexander stood off in the distance, watching his younger brother with a mixture of curiosity and awe. Michael was a beautiful man-child, incredibly graceful and athletic, strong beyond belief. He wore a black pocket T-shirt and powder blue shorts. He was already six feet three and a hundred eighty-five pounds. He was flawless. Both of them were, actually.

William walked away, staring into the distance at the rich, green hills. He loved it out here. The beauty and the solitude, the freedom to do anything he wanted to do.

He was very quiet inside— an art that he was still mastering.

When he and Michael were small boys, this whole area had been a commune. Their mother and father had been hippies, experimenters, freedom lovers, massive drug takers. They had instructed the boys that the outside world was not only dangerous but also wrong. Their mother had taught William and Michael that having sex with anyone, even with her, was a good thing, as long as it was consensual. The brothers had slept with their mother, and their father, and many others in the commune. Their code of personal freedom had turned bad and eventually got them two years at a Level IV correctional facility. They had been arrested for possession, but it was aggravated assault that put the brothers behind bars. They were suspected of much more serious crimes, but none could be proved.

As William stared off at the foothills, he marveled at the concept of the unbridled mind. Day by day he left behind the shabby baggage of his past life. Soon he would have no false morals, or ethics, or any of the other bullshit inhibitions taught in the civilized world.

He was getting closer to the truth. So was Michael.

William was twenty.

Michael was only seventeen.

They had been killing together for five years, and they kept getting better and better at it.

They were invincible.

Immortal.

That night, the two brothers hunted in the town of Mill Valley, in Marin County. The area was beautiful, small mountains teeming with strapping, healthy evergreen and eucalyptus trees. The redwood house was maybe a hundred yards ahead, up a steep, rocky slope that they climbed with ease. A brick walkway led to an entryway with double wooden doors.

"We have to go away for a while." William spoke to Michael without turning around. "We have a mission from the Sire. San Francisco was just the start."

"That's excellent," Michael said, and he smiled. "I enjoyed what went down there very much. Who are these people, the ones in the big fancy house up there?"

William shrugged. "Just prey. They're nobody." Michael pouted. "Why won't you tell me who they are?"

"The Sire said not to talk, and not to bring the cat."

Michael asked no further questions. His obedience to the Sire was complete. The Sire told you how to think, feel, and act.

The Sire was accountable to no one, to no other authority.

The Sire despised the straight world, as did they.

This definitely looked like the "straight world" up ahead. The large house had all the trappings: gardens tended and watered daily, a small pond filled with koi, several layers of terraces leading up to a large house with more than a dozen rooms — for just two people. How obnoxious could anyone be?

William walked right in the front door, and Michael followed. The foyer had twenty-foot ceilings, a ridiculous crystal chandelier, a spiral staircase to heaven.

They found the couple in the kitchen, making a late meal, both of them sharing the preparations like the goody-goodies that they were.

"Yuppies at play," William said, and smiled.

"Whoa!" the male said, and threw up both of his hands. He was close to six-four and well built. He was working like kitchen help at the vegetable sink.

"What the hell do you guys think you're doing? Let's take it outside."

"You'rethe troublemaking lawyer," William said, and pointed at the female. She was early thirties, short blond hair, high cheekbones, slender, with small breasts. "We came for supper."

"I'm a lawyer too," the domineering male said. "I don't think you two were invited. I'm sure of it. Get out! You hear me? Hey, you assholes, hit the road."