"Not necessarily. There are many ancient inscriptions that stand alone without parallel symbols. Believe me when I say the signs on the walls in the chamber of the black skull are unique."

"Any chance they might be a deception?"

"I won't know until I have a chance to study them in depth."

"Take it from me," Marquez stated emphatically, "no one had entered that chamber before me in a long time. The surrounding rock showed no signs of recent digging."

Pat brushed her long red hair from her eyes. "The puzzle is who built it and why."

"And when," Pitt threw in. "Somehow the chamber and the killers are tied together."

A sudden breeze whistled up the canyon, rattling the windows of the solarium. Pat shivered. "The evening is getting cool. I think I'll get my coat."

Marquez turned toward the kitchen. "I wonder where Lisa is with the coffee and cake-"

His voice broke off as Pitt suddenly leaped to his feet. In one convulsive movement, he shoved the miner under the log table, then seized Pat and threw her to the wooden floor, covering her body with his own. Some alien wisp of movement in the shadows beside the house had tweaked the acute sense of menace that had been honed in him over the years. In the next instant, two explosions of gunfire burst from the shadows outside, coming so close together, they sounded as one.

Pitt lay there on Pat, hearing her gasp for the breath he had knocked from her chest. He rolled off her and came to his feet as he heard a familiar voice shout from the evening shadows, a voice distinct with an a.s.sured confidence.

"Got him!"

Pitt slowly helped Pat to a chair and pulled Marquez to his feet. "Those were gunshots ... that voice?" murmured a dazed Marquez.

"Not to worry," Pitt said rea.s.suringly. "The posse is on our side."

"Lisa, my kids," Marquez blurted, turning and starting to run into the house.

"Safe in the bathtub," said Pitt, grabbing an arm.

"How-?"

"Because that's where I told them to hide."

A stocky bull of a man materialized from the mountain undergrowth surrounding the house, wearing an Arctic white jumpsuit with a hood. He was dragging a body through the snow, dressed in a black ninja suit, its face covered by a ski mask. There was still enough light left in the sky to see the white-clad man's s.h.a.g of black curly hair, dark Etruscan eyes, and lips spread in a white-toothed grin. He pulled the body along by one foot as effortlessly as if he were hauling a ten-pound bag of potatoes.

"Any problems?" asked Pitt quietly, stepping outside into the snow-covered yard.

"None," answered the stranger. "Like mugging a blind man. Despite a masterful attempt at a sneaky intrusion, the last thing he expected was an ambush."

"Underrating his intended prey is the worst miscalculation a professional killer can make."

Pat gazed at Pitt, ashen-faced. "You planned this?" she uttered mechanically.

"Of course," Pitt admitted, almost fiendishly. "The killers are ..." He paused to look down at the man lying at his feet. "Or, rather, were fanatics. I can't begin to guess what lies behind their motive to kill anyone who entered that mysterious chamber. In my case, I moved to the head of their kill list when I showed up out of the blue and put a wrench in their well-oiled plan. They were also afraid I might return to the chamber and retrieve the black skull. Their fear of Pat was that she might decipher the inscriptions.

"After we escaped the tunnel and were released by Sheriff Eagan, this one stood back and watched us, waiting for the right opportunity. Because they had already made such a prolonged effort to hide the chamber discovery by eliminating all witnesses, it didn't take a cla.s.s in village idiocy to figure they were not about to leave the job undone and allow any of us to leave Telluride alive. So I threw out the bait and reeled them in."

"You set us up as decoys," muttered Marquez. "We might have been killed."

"Better to take that risk now while the cards are on our side of the table than to wait until we're vulnerable."

"Shouldn't Sheriff Eagan be in on this?"

"As we speak, he should be apprehending the other killer at Pat's bed-and-breakfast."

"A gunman in my room?" Pat uttered in a shocked whisper. "While I was taking a bath?"

"No," Pitt said patiently. "He entered only after you left for the Marquez house with me."

"But he could have walked right in and murdered me."

"Not hardly." Pitt squeezed her hand. "Trust me when I say there was little danger. Didn't you notice the place was a little crowded? The sheriff arranged for a small throng of locals to roam the halls and dining rooms of the bed-and-breakfast, acting like conventioneers. It would have been awkward for a stalking killer to take his victim in a crowd. When it was advertised that you and I both were coming to the Marquezes' for dinner, the killers split the operation. One volunteered to send us all to the cemetery during dinner, while the other tossed your room for your notebook and camera."

"He doesn't look like anyone I know with the sheriff's department," said Marquez, pointing to the muscular intruder.

Pitt turned and placed his arm around the shoulders of the stranger who had just subdued the a.s.sa.s.sin. "May I present my oldest and dearest friend, Albert Giordino. Al is my a.s.sistant projects director with NUMA."

Marquez and Pat stood silently, uncertain of how to act. They studied Al with the intent of a bacterial researcher peering through a microscope at a specimen. Giordino simply released his grip on the intruder's foot, stepped forward, and shook their hands. "A pleasure to meet you both. I'm happy to have been of service."

"Who got shot?" Pitt queried.

"This guy had reactions you can't believe," said Giordino.

"Oh, yes, I can."

"He must have been psychic. He snapped off a shot in my direction the same instant I squeezed my own trigger." Giordino pointed to a slight tear along the hip of his jumpsuit. "His bullet barely bruised my skin. Mine took him in the right lung."

"You were lucky."

"Oh, I don't know," Giordino said loftily. "I aimed, he didn't."

"Is he still alive?"

"I should think so. But he won't be entering a marathon anytime soon."

Pitt leaned down and pulled the ski mask from the killer's head.

Pat gasped in horror-understandable, considering the circ.u.mstance, Pitt thought wryly. She still found it impossible to accept everything that had happened to her since stepping off the plane at the Telluride airport.

"Oh, dear G.o.d!" Her voice held a mixture of shock and distress. "It's Dr. Ambrose!"

"No, dear lady," Pitt said softly. "That is not Dr. Thomas Ambrose. As I told you before, the real Ambrose is probably dead. This lowlife probably took on the job of murdering you and me and Luis because only he could identify us with any certainty."

The truth of Pitt's words struck her with numbing cruelty. She knelt down and looked into the open eyes of the killer and demanded, "Why did you have to murder Dr. Ambrose?"

There was no flicker of emotion in the killer's eyes. The only indication of injury was the blood trickling from his mouth, a sure sign of a lung wound. "Not murdered, executed," he whispered. "He was a threat and had to die, just as you must all die."

"You have the guts to justify your actions," Pitt said, with an icy edge to his voice.