Audrey asked me to stay. Shawn was too strong, she said, too persuasive, for her to confront him alone. I told her she wasn't alone, she had Mother. Audrey said I didn't understand. No one had believed us after all. If we asked Dad for help, she was sure he'd call us both liars. I told her our parents had changed and we should trust them. Then I boarded a plane and took myself five thousand miles away.

I didn't stay long on Buck's Peak, maybe a week. On the day I left the mountain, Audrey asked me not to go. I have no memory of the conversation, but I remember writing the journal entry about it. I wrote it my first night back in Cambridge, while sitting on a stone bridge and staring up at King's College Chapel. I remember the river, which was calm; I remember the slow drift of autumn leaves resting on the glassy surface. I remember the scratch of my pen moving across the page, recounting in detail, for a full eight pages, precisely what my sister had said. But the memory of her saying it is gone: it is as if I wrote in order to forget.

If I felt guilty to be documenting my sister's fears from such a safe distance, surrounded by grand libraries and ancient chapels, I gave only one indication of it, in the last line I wrote that night: Cambridge is less beautiful tonight.

But to write what? While reading for my master's thesis, I'd been surprised to discover echoes of Mormon theology in the great philosophers of the nineteenth century. I mentioned this to David Runciman, my supervisor. "That's your project," he said. "You can do something no one has done: you can examine Mormonism not just as a religious movement, but as an intellectual one."

The first term passed in a flurry of dinners and late-night parties, punctuated by even later nights in the library. To qualify for a PhD, I had to produce a piece of original academic research. In other words, having spent five years reading history, I was now being asked to write it.

Drew had come with me to Cambridge, having been admitted to a master's program in Middle Eastern studies. I told him about my conversation with Audrey. He was the first boyfriend in whom I confided about my family -- really confided, the truth and not just amusing anecdotes. Of course all that is in the past, I said. My family is different now. But you should know. So you can watch me. In case I do something crazy.

But although I wished it were otherwise, I did not want to go home. I preferred the family I had chosen to the one I had been given, so the happier I became in Cambridge, the more my happiness was made fetid by my feeling that I had betrayed Buck's Peak. That feeling became a physical part of me, something I could taste on my tongue or smell on my own breath.

I began to reread the letters of Joseph Smith and Brigham Young. As a child I'd read those letters as an act of worship; now I read them with different eyes, not the eyes of a critic, but also not the eyes of a disciple. I examined polygamy, not as a doctrine but as a social policy. I measured it against its own aims, as well as against other movements and theories from the same period. It felt like a radical act.

My friends in Cambridge had become a kind of family, and I felt a sense of belonging with them that, for many years, had been absent on Buck's Peak. Sometimes I felt damned for those feelings. No natural sister should love a stranger more than a brother, I thought, and what sort of daughter prefers a teacher to her own father?

I bought a ticket to Idaho for Christmas. The night before my flight, there was a feast in my college. One of my friends had formed a chamber choir that was to sing carols during dinner. The choir had been rehearsing for weeks, but on the day of the feast the soprano fell ill with bronchitis. My phone rang late that afternoon. It was my friend. "Please tell me you know someone who can sing," he said.

I had not sung for years, and never without my father to hear me, but a few hours later I joined the chamber choir on a platform near the rafters, above the massive Christmas tree that dominated the hall. I treasured the moment, taking pleasure in the lightness I felt to have music once again floating up from my chest, and wondering whether Dad, if he were here, would have braved the university and all its socialism to hear me sing. I believed he would.

Buck's peak was unchanged. The Princess was buried in snow but I could see the deep contours of her legs. Mother was in the kitchen when I arrived, stirring a stew with one hand and with the other holding the phone and explaining the properties of motherwort. Dad's desk was still empty. He was in the basement, Mother said, in bed. Something had hold of his lungs.

Two days passed. Dad came upstairs every evening and settled himself into a sofa in the Chapel, where he would cough and watch TV or read the Old Testament. I spent my days studying or helping Mother.

A burly stranger shuffled through the back door. Several seconds passed before I recognized my brother. Luke's beard was so thick, he looked like one of his goats. His left eye was white and dead: he'd been shot in the face with a paintball gun a few months before. He crossed the room and clapped me on the back, and I stared into his remaining eye, looking for something familiar. But it wasn't until I saw the raised scar on his forearm, a curved check mark two inches wide from where the Shear had bitten his flesh, that I was sure this man was my brother. He told me he was living with his wife and a pack of kids in a mobile home behind the barn, making his money working oil rigs in North Dakota.

On the third evening I was at the kitchen table, reading, when Shawn and Benjamin shuffled through the back door. Benjamin was telling Shawn about a punch he'd thrown after a fender bender in town. He said that before climbing out of his truck to confront the other driver, he'd slipped his handgun into the waistband of his jeans. "The guy didn't know what he was getting into," Benjamin said, grinning.

"I wasn't gonna use it," Benjamin muttered.

Shawn spoke calmly, thoughtfully. His blond hair was filthy and uncut, growing wild, and his face was covered in stubble the color of shale. His eyes shone from under the oil and dirt, blazes of blue in clouds of ash. His expression, as well as his words, seemed to belong to a much older man, a man whose hot blood had cooled, who was at peace.

"Only an idiot brings a gun into a mess like that," Shawn said.

"Then don't bring it," Shawn said. "Then you know you won't use it. If you bring it you might use it, that's how things are. A fistfight can turn into a gunfight real quick."

Shawn turned to me. I had been avoiding him, but suddenly that seemed unfair. He had changed; it was cruel to pretend he hadn't. He asked if I'd like to go for a drive, and I said I would. Shawn wanted ice cream so we got milkshakes. The conversation was calm, comfortable, like it had been years before on those dusky evenings in the corral. He told me about running the crew without Dad, about Peter's frail lungs -- about the surgeries and the oxygen tubes he still wore at night.

"Where we going?" I asked, but the road only went one place.

We were nearly home, only a mile from Buck's Peak, when Shawn cranked the wheel and the car skidded on the ice. He accelerated through the spin, the tires caught, and the car leapt onto a side road.

Shawn circled the lot, then parked near the main entrance. He switched off the ignition and the headlights faded. I could barely make out the curve of his face in the dark.

The church was dark, the parking lot deserted.

"You talk much to Audrey?" he said.

"Not really," I said.

I looked away, fixing my eyes on the church spire, visible against the light from the stars.

He seemed to relax, then he said, "Audrey is a lying piece of shit."

It was crucial that I not look at him. As long as I kept my eyes on the spire, I almost believed he couldn't touch me. Almost. Because even while I clung to this belief, I waited to feel his hands on my neck. I knew I would feel them, and soon, but I didn't dare do anything that might break the spell of waiting. In that moment part of me believed, as I had always believed, that it would be me who broke the spell, who caused it to break. When the stillness shattered and his fury rushed at me, I would know that something I had done was the catalyst, the cause. There is hope in such a superstition; there is the illusion of control.

"I'd put a bullet in her head," Shawn said, and I felt his body shift toward me. "But I don't want to waste a good bullet on a worthless bitch."

"You feel like a movie?" Shawn said. His voice was casual. I watched the world revolve as the car spun around and lurched back to the highway. "A movie sounds just right," he said.

The ignition clicked, the engine growled to life. Warm air flooded through the vents.

I said nothing, unwilling to move or speak lest I offend the strange sorcery of physics that I still believed had saved me. Shawn seemed unaware of my silence. He drove the last mile to Buck's Peak chatting cheerfully, almost playfully, about whether to watch The Man Who Knew Too Little, or not.

I stayed still, without thought or motion.