WHAT WE SEE THROUGH THE DOORWAY IS A scene from a nightmare. This time, though, it's not my own personal hell, but a tableau from an ancient book on witchcraft. A huge fire crackles and dances, sending sparks and laps of flame into the night. The reflection cast by the fire is the only light, making the darkness beyond dense and impenetrable. In the flickering shadows, an altar rises like a specter, and something that looks very much like a gallows. There is a form suspended on the scaffold, not hanging from a noose, but spread-eagle on a cross. It looks human. And it's very still.

Frey stops me from moving forward by taking my hand gently into his mouth. I'm so intent on trying to make sense of the scene, I almost blunder into the trap. A thin wire stretches ankle height across the door. We can't see what it would trip, but it doesn't matter. I step over while Frey leaps it with feline gracefulness.

The chanting comes from our right, out of sight behind an outcropping of rock. It's a melodious, ancient sound that reminds me of the old Catholic high mass. Latin, maybe, or Celtic. It's accompanied by an instrument with sweet, clear tones. A recorder.

Frey and I scramble across a bare expanse of ground to take shelter behind a rock. I don't know if we're in Mexico or have crossed into the United States. Most of these tunnels exit somewhere in the Otay Mesa area of San Diego County, but I haven't a clue how far we traveled.

I peek up from the rock, keeping as still as I can to avoid attracting attention. My breath catches in my throat when I recognize what is hanging from that cross. There are two bodies, back to back, lashed together. One, facing me, is a woman, her limp, naked body a pale, flickering silhouette in the firelight. I can't make out the other. I can't even tell whether the two are human, although I suspect they are.

Or if they are alive.

Where is Culebra?

The chanting becomes louder, more urgent. I glance at my watch-it's ten minutes before midnight. I'd lost track of time. We must have traveled much farther than I imagined.

I shift my gaze in the direction of the sound. Dozens of people form a hellish chorus, standing close together, dressed in long dark robes with the cowls pulled over their heads. They sway and moan the words, caught up in some demonic rapture.

A woman steps from the group, opens her robe, lets it fall to the ground. She has dark hair that sweeps forward to cover her face. Her naked body glows in the reflected light. When she turns toward the altar, I see it. On her right shoulder is a tattoo. A crimson skull with a rose. Belinda Burke.

At a signal from the witch, the others let their robes fall, too. Now, men and women, all stand naked. They intertwine hands and follow as she makes her way toward the altar. She alone climbs the steps. Still chanting, the others form a circle around the fire and the altar.

Belinda Burke looks down on her congregation. She raises a staff and they grow quiet.

"We have taken the first step," she says, her words infused with a dark energy that makes a shiver touch my spine. "The gathering is complete. The hour approaches. We will accomplish what no other coven has done before. We will summon the demon, Aswah, and he will be our servant. He will cleanse the earth of those who hide themselves among us, pretending to be human, pretending to do us no harm."

She gestures to the cross behind her. "We will seal this pact with the offerings. A human woman, to show Aswah what earthly pleasures await him. And the demon, shapeshifter, to remind him of his mission."

My body tenses as her words stab at my heart. Culebra? Is it you?

There is no answer from the motionless figure. How could this have happened? Culebra is powerful, possesses strong magic. How could he have let himself be trapped by a witch?

Burke is still talking, but I no longer listen. I've got to stop this. I feel Frey shift beside me, his eyes hold a question I can't yet answer.

Burke raises the staff again. The coven responds. The chanting is louder, more compelling, filled with the zealousness of renewed purpose. Burke's voice floats out over the others, intoning the summoning spell. The fire leaps higher as if in response to her words. The ground begins to shake beneath our feet.

It's two minutes to midnight. Think. What did Williams say? There is only an instant when the summoning can be completed, when the worlds of the living and dead overlap. We have to interrupt at that instant.

The fire parts, dividing itself to form a chasm in the pit. Burke's face is wild with desire, her voice shakes with emotion. She is caught up in a frenzy of excitement and joy. Her feelings reach out across the coven, sucking them in, increasing their own passion. I feel it, too. Watch in wonder at the power that springs forth from the gathering. I'm drawn in, thrilled by an almost sexual longing to be a part of what is happening. I stand up, ready to join them, ready to raise my voice in welcome to-

Frey snaps at me, biting down hard on my arm.

I jump at the pain, whirl to face my attacker.

Frey growls and snaps again.

Blood, my blood, runs freely down the length of my right arm. The sight and smell of it clears my head in an instant.

The minute hand of my watch sweeps toward midnight. Thirty seconds.

I start to run, across the ground, clearing the distance in a heartbeat. Frey is in front of me. He hesitates only a second and I point to the person closest to him, just yards away. He launches himself at the same time I throw all my weight against the circle, breaking the bond between outstretched hands. A lightning bolt of power passes through me and I stumble from the impact. Then it flows out of me and into the ground, and the chanting stops.

There is a roar. Animal-like and ferocious. I whirl toward the sound. The fire in the pit closes around something scrambling to escape. A huge creature, black, red eyes, sharp-tipped horns glistening. The mouth is open, screaming in rage and fear. Its eyes turn in my direction, its gaze burning into my soul, knowing, blaming me for what is happening. It reaches a clawlike hand toward me, to draw me into the pit. I feel myself moving forward. I dig in my heels, but I can't stop. It smiles, a ghastly grin that shows fangs and a forked tongue, and I know. It recognizes that I am vampire and it will have its revenge. I'm at the very edge of the pit. My clothes are burning, the heat singes my skin.

With an explosion of ash and flame, the fire collapses in on itself. The demon is drawn down, howling with frustration, back into the pit. I'm thrown to the ground with bone jarring force. The earth beneath our feet roils and stirs as if revolting against the demon it's being forced to take back. With one last violent shudder, it grows still.

I collapse back, relieved, and rest my head against the ground while I collect my thoughts. We stopped the demon. Frey and I.

Where is Frey?

I push myself up on my elbows and look around.

I'm surrounded by an angry coven, pushing closer, their rage palpable as they close the circle around me.

"Vampire."

Burke's voice draws my eyes to the altar.

She's standing at the foot of the cross, a crossbow in her hand. At her feet, a still, dark form.

My heart leaps.

Frey.

She nudges him with her foot. But he doesn't move or make a sound. The bolt in his side says it all.