“So you'd need a whole lot of spiders to produce a reasonable amount of venom?”

“Probably,” she replied.

I wondered how many spiders had been milked in order to kill Yossi Epstein. I also wondered why anyone would bother. After all, it would have been far easier, and less conspicuous, simply to have killed Epstein in a more conventional way. Then I remembered Alison Beck, and how she must have felt as the widows struggled in her mouth and the recluses moved around her in the small, enclosed space of the car. I recalled the look in Mickey Shine's eyes as he spoke of the spiders in the bathtub, and the wounds gouged in his skin by their bites. And I thought of my own feelings as the blisters appeared on my skin, and the sensation of Mr. Pudd's thin, hairy fingers brushing against my own.

He did it because it was fun, because he was genuinely curious about the effects. He did it because to be preyed upon by a small, dark, consuming creature, multilegged and many-eyed, terrified his victims in ways that a bullet or a knife could not, and gave a new intensity to their sufferings. Even Epstein, who endured death by injection, had felt something of this pain as his muscles spasmed and cramped, his breathing began to fail, and his heart at last gave way under the pressure on his body.

It was also a message. I was certain of that. And the only person for whom that message could be meant was Jack Mercier. Epstein and Beck were in the photograph on his wall, and Warren Ober's law firm had been handling Epstein's legal challenge to the IRS tax exemption granted to the Fellowship. I knew then that I had to return to Maine, that somehow Grace Peltier's death was linked to moves that her father and others had been making against the Fellowship. But how could Pudd and those who aided him have known that Grace Peltier was Jack Mercier's daughter? There was also the question of how a woman who was researching the history of a long-departed religious group ended up trying to corner the leader of the Fellowship. I could only find one answer: someone had pointed Grace Peltier in the direction of the Fellowship, and she had died because of it.

I tried calling Mercier again as Rachel went to take a shower, but I got the same maid and a promise that Mr. Mercier would be told that I had called. I asked for Quentin Harrold and was similarly informed that he was not available. I was tempted to throw my cell phone to the ground and stamp on it, but I figured I might need it, so I contented myself with tossing it in disgust on Rachel's couch. It wasn't as if I had anything to tell Mercier anyway, or certainly nothing that he didn't already know. I just didn't like being kept in the dark, especially when Mr. Pudd was occupying space in that same darkness.

But there was another reason that I had yet to learn for Mr. Pudd's killing methods, a tenet that had its roots in the distant past, and in other, older traditions.

It was the belief that spiders were the guardians of the underworld.

The Wang Center, on Tremont, was just about the most beautiful theater on the upper East Coast, and the Boston Ballet was, given my limited experience, a great company, so the combination was pretty hard to resist, especially on a first night. As we walked past Boston Common, a band played in the window of Emerson College's WERS radio station, the crowds heading to the theater district pausing briefly to examine the contorted face of the singer. We collected our tickets at the box office and walked into the ornate marble and gold lobby, past the booths hawking Cleopatra memorabilia and souvenir books. We had seats in the front row, far left, of the orchestra box-close to the back of the theater and slightly raised above the rows of seats ahead, so that nobody could obscure our view. The red and gold of the theater was almost as opulent as the stage design, giving the whole affair an air of restrained decadence.

“You know, when I told Angel we were coming here he asked me if I was sure I wasn't gay,” I whispered to Rachel.

“What did you say?”

“I told him I wasn't dancing the damn ballet, I was just going to watch it.”

“So I'm just a means of reassuring you about your heterosexuality?” she teased.

“Well, a very pleasurable means…”

Above and to my right, a figure entered one of the front-row seats on the level above ours, at the farthest extremity of the U-shaped upper tier. He moved slowly, easing himself gently into his chair before adjusting his hearing aids. Behind him, Tommy Caci folded Al Z's coat, then poured a glass of red wine for his boss before taking the seat directly behind him.

The Wang is an egalitarian theater; there are no closed boxes, but some sections are more private than others. The area where Al Z sat was known as the Wang box; it was partially shielded by a pillar, although it was open to the aisle on the right. The adjacent seats were empty, which meant that Al had booked the entire section for the first-night show.

Al Z, I thought, you old romantic.

The lights went down as the audience grew quiet. Rimsky-Korsakov's music, arranged for the ballet by the composer John Lanchbery, filled the huge space as the evening's entertainment commenced. Handmaidens danced around Cleopatra's bedchamber while the queen slept in the background and her brother Ptolemy and his confidant Pothinus plotted her downfall. It was all brilliantly done, yet I found myself drifting during the whole first half, my mind occupied by images of crawling things and the final, imagined moments of Grace Peltier's life. I kept seeing:

A gun close to her head, a hand buried in her hair to hold her steady as a finger tightened on the trigger. It is her finger, but pressed against it is another. She is dazed, stunned by a blow to the temple, and cannot fight as her arm is maneuvered into position. There is no blood from the blow, and anyway the entry wound will tear apart the skin and bone, disguising any earlier injury. It is only when the cold metal touches her skin that she realizes, finally, what is happening. She strikes out and opens her mouth to scream…

There is a roar in the night, and a red flame bursts from her head and sheds itself over the window and the door. The light dies in her eyes and her body slumps to the right, the smell of burning in the air as her singed hair hisses softly.

There is no pain.

There will never be pain again.

I felt a pressure on my arm and found Rachel looking at me quizzically, the ballet on stage reaching its preintermission climax. In her bedchamber, Cleopatra was dancing for Caesar, seducing him. I patted Rachel's hand and saw her scowl at the patronizing nature of the gesture, but before I could explain, a movement to my far right attracted my attention. Tommy Caci had risen, distracted, and was reaching inside his jacket. Before him, Al Z continued watching the ballet, apparently unaware of what was going on behind. Tommy moved away from his seat and disappeared into the aisle.

Onstage, the assassin, Pothinus, appeared in the wings, looking for his moment to strike at the queen, but Cleopatra and Caesar danced on, oblivious. The music swelled as a figure took the seat behind Al Z, but it was not Tommy Caci. Instead, it was thinner, more angular. Al Z remained engrossed in the action, his head moving in time to the music, his mind filled with images of escape as he sought briefly to forget the darker world he had chosen to inhabit. A hand moved, and something silver gleamed. Pothinus shot out from the wings, sword in hand, but Caesar was quicker and his sword impaled Pothinus through the stomach.

And in the box above, Al Z's body tensed and fluid shot from his mouth as the figure leaned over him, one hand on his shoulder, the other close to the base of his skull. From behind, it would appear as if they were talking, nothing more, but I had seen the blade flash, and I knew what had happened. Al Z's mouth was wide open, and as I watched, Mr. Pudd's gloved hand closed upon it and he held him as he shook and died.