Somehow I got back into my building, then I sat on my bed and tried to reconstruct what had happened. I remembered going to sleep. I remembered the dream. What I did not remember was flying from my bed and sprinting down the hall and into the street, shouting, but that is what I had done.

The dream had been of home. Dad had built a maze on Buck's Peak and trapped me inside it. The walls were ten feet high and made of supplies from his root cellar -- sacks of grain, cases of ammunition, drums of honey. I was searching for something, something precious I could never replace. I had to escape the maze to recover it, but I couldn't find the way out, and Dad was pursuing me, sealing the exits with sacks of grain stacked into barricades.

Someone was screaming, a long, steady holler, so loud it woke me up. It was dark. There were streetlights, pavement, the rumble of distant cars. I was standing in the middle of Oxford Street, half a block from my dorm room. My feet were bare, and I was wearing a tank top and flannel pajama bottoms. It felt like people were gawking at me, but it was two in the morning and the street was empty.

I did not study. I tried to read but the sentences meant nothing. I needed them to mean nothing. I couldn't bear to string sentences into strands of thought, or to weave those strands into ideas. Ideas were too similar to reflection, and my reflections were always of the expression on my father's stretched face the moment before he'd fled from me.

The thing about having a mental breakdown is that no matter how obvious it is that you're having one, it is somehow not obvious to you. I'm fine, you think. So what if I watched TV for twenty-four straight hours yesterday. I'm not falling apart. I'm just lazy. Why it's better to think yourself lazy than think yourself in distress, I'm not sure. But it was better. More than better: it was vital.

I stopped going to my French group, then to my sketching class. Instead of reading in the library or attending lectures, I watched TV in my room, working my way through every popular series from the past two decades. When one episode ended, I would begin the next without thinking, the way one breath follows another. I watched TV eighteen or twenty hours a day. When I slept I dreamed of home, and at least once a week I awoke standing in the street in the middle of the night, wondering if it was my own cry that I'd heard just before waking.

After a few more weeks of this, I stumbled from my bed one night and decided that I'd made a mistake, that when my father had offered me the blessing, I should have accepted it. But it wasn't too late. I could repair the damage, put it right.

By December I was so far behind in my work that, pausing one night to begin a new episode of Breaking Bad, I realized that I might fail my PhD. I laughed maniacally for ten minutes at this irony: that having sacrificed my family to my education, I might lose that, also.

I purchased a ticket to Idaho for Christmas. Two days before the flight, I awoke in a cold sweat. I'd dreamed I was in a hospital, lying on crisp white sheets. Dad was at the foot of the gurney, telling a policeman I had stabbed myself. Mother echoed him, her eyes panicked. I was surprised to hear Drew's voice, shouting that I needed to be moved to another hospital. "He'll find her here," he kept saying.

I wrote to Drew, who was living in the Middle East. I told him I was going to Buck's Peak. When he replied his tone was urgent and sharp, as if he was trying to cut through whatever fog I was living in. My dear Tara, he wrote. If Shawn stabs you, you won't be taken to a hospital. You'll be put in the basement and given some lavender for the wound. He begged me not to go, saying a hundred things I already knew and didn't care about, and when that didn't work, he said: You told me your story so I could stop you if you ever did something crazy. Well, Tara, this is it. This is crazy.

It was a bright winter morning when I arrived on Buck's Peak. I remember the crisp smell of frozen earth as I approached the house and the feel of ice and gravel crunching beneath my boots. The sky was a shocking blue. I breathed in the welcome scent of pine.

My gaze dropped below the mountain and my breath caught. When Grandma had been alive, she had, by nagging, shouting and threats, kept my father's junkyard contained. Now refuse covered the farm and was creeping toward the mountain base. The rolling hills, once perfect lakes of snow, were dotted with mangled trucks and rusted septic tanks.

I can still fix this, I chanted as the plane lifted off the tarmac.

Mother was ecstatic when I stepped through the door. I hadn't told her I was coming, hoping that, if no one knew, I might avoid Shawn. She talked rapidly, nervously. "I'm going to make you biscuits and gravy!" she said, then flew to the kitchen.

"I'll help in a minute," I said. "I just need to send an email."

The family computer was in the old part of the house, what had been the front room before the renovation. I sat down to write Drew, because I'd promised, as a kind of compromise between us, that while on the mountain I would write to him every two hours. I nudged the mouse and the screen flickered on. The browser was already open; someone had forgotten to sign out. I moved to open a different browser but stopped when I saw my name. It was in the message that was open on the screen, which Mother had sent only moments before. To Shawn's ex-girlfriend Erin.

The premise of the message was that Shawn had been reborn, spiritually cleansed. That the Atonement had healed our family, and that all had been restored. All except me. The spirit has whispered to me the truth about my daughter, Mother wrote. My poor child has given herself over to fear, and that fear has made her desperate to validate her misperceptions. I do not know if she is a danger to our family, but I have reasons to think she might be.

There was more to the email. In the final paragraph, Mother described the birth of Emily's second child, a daughter, who had been born a month before. Mother had midwifed the child. The birth had taken place at home and, according to Mother, Emily had nearly bled to death before they could get to a hospital. Mother finished the story by testifying: God had worked through her hands that night, she said. The birth was a testament of His power.

I had known, even before reading the message, that my mother shared my father's dark vision, that she believed the devil had a hold of me, that I was dangerous. But there was something in seeing the words on the page, in reading them and hearing her voice in them, the voice of my mother, that turned my body cold.

If the first fall was God's will, whose was the second?

I remembered the drama of Peter's birth: how he'd slipped out of Emily weighing little more than a pound; how he'd been such a shocking shade of gray, they'd thought he was dead; how they'd fought through a snowstorm to the hospital in town, only to be told it wasn't enough, and there were no choppers flying; how two ambulances had been dispatched to McKay-Dee in Ogden. That a woman with this medical history, a woman so obviously high-risk, should be advised to attempt a second birth at home seemed reckless to the point of delusion.

I was still wondering at the birth of my niece when Erin's response appeared. You are right about Tara, she said. She is lost without faith. Erin told Mother that my doubting myself -- my writing to her, Erin, to ask if I might be mistaken, if my memories might be false -- was evidence that my soul was in jeopardy, that I couldn't be trusted: She is building her life on fear. I will pray for her. Erin ended the message by praising my mother's skill as a midwife. You are a true hero, she wrote.

I remembered the dream, the maze. I remembered the walls made of grain sacks and ammunition boxes, of my father's fears and paranoias, his scriptures and prophecies. I had wanted to escape the maze with its disorienting switchbacks, its ever-modulating pathways, to find the precious thing. But now I understood: the precious thing, that was the maze. That's all that was left of the life I'd had here: a puzzle whose rules I would never understand, because they were not rules at all but a kind of cage meant to enclose me. I could stay, and search for what had been home, or I could go, now, before the walls shifted and the way out was shut.

Mother was sliding biscuits into the oven when I entered the kitchen. I looked around, mentally searching the house. What do I need from this place? There was only one thing: my memories. I found them under my bed, in a box, where I had left them. I carried them to the car and put them in the backseat.

I closed the browser and stared at the wallpaper behind the screen. It was the same floral print from my childhood. For how long had I been dreaming of seeing it? I had come to reclaim that life, to save it. But there was nothing here to save, nothing to grasp. There was only shifting sand, shifting loyalties, shifting histories.

"I do," I said. "That has never been the issue."

"I'm going for a drive," I told Mother. I tried to keep my voice smooth. I hugged her, then took a long look at Buck's Peak, memorizing every line and shadow. Mother had seen me take my journals to the car. She must have known what that meant, must have sensed the farewell in it, because she fetched my father. He gave me a stiff hug and said, "I love you, you know that?"

I hadn't spoken to my brother in months -- after what happened with Audrey, it had seemed pointless to confide in my siblings. I was sure Mother would have told every brother, cousin, aunt and uncle the story she had told Erin: that I was possessed, dangerous, taken by the devil. I wasn't wrong: Mother had warned them. But then she made a mistake.

Those words are the last I said to my father.

After I left Buck's Peak, she panicked. She was afraid I might contact Tyler, and that if I did, he might sympathize with me. She decided to get to Tyler first, to deny anything I might tell him, but she miscalculated. She didn't stop to think how the denials would sound, coming from nowhere like that.

I drove south; I didn't know where I was going. It was nearly Christmas. I had decided to go to the airport and board the next flight to Boston when Tyler called.

I thought he'd say I was lying but he didn't. He accepted almost immediately the reality I'd spent a year denying. I didn't understand why he was trusting me, but then he told me his own stories and I remembered: Shawn had been his older brother, too.

"Of course Shawn didn't stab Diego and threaten Tara with the knife," Mother reassured Tyler, but to Tyler, who had never heard any part of this story, not from me or anyone else, this was somewhat less than reassuring. A moment after he said goodbye to Mother, Tyler called me, demanding to know what had happened and why I hadn't come to him.

In the weeks that followed, Tyler began to test my parents in the subtle, nonconfrontational way that was uniquely his. He suggested that perhaps the situation had been mishandled, that perhaps I was not possessed. Perhaps I was not evil at all.

I might have taken comfort in Tyler's trying to help me, but the memory of my sister was too raw, and I didn't trust him. I knew that if Tyler confronted my parents -- really confronted them -- they would force him to choose between me and them, between me and the rest of the family. And from Audrey I had learned: he would not choose me.

My fellowship at Harvard finished in the spring. I flew to the Middle East, where Drew was completing a Fulbright. It took some effort, but I managed to hide from Drew how poorly I was doing, or at least I thought I did. I probably didn't. He was, after all, the one chasing me through his flat when I awoke in the middle of the night, screaming and sprinting, with no idea where I was but a desperate need to escape it.

We left Amman and drove south. We were in a Bedouin camp in the Jordanian desert on the day the navy SEALs killed bin Laden. Drew spoke Arabic, and when the news broke he spent hours in conversation with our guides. "He's no Muslim," they told Drew as we sat on cold sand watching the dying flames of a campfire. "He does not understand Islam, or he would not do the terrible things he's done."

I watched Drew talk with the Bedouins, heard the strange, smooth sounds falling from his lips, and was struck by the implausibility of my presence there. When the twin towers had fallen ten years before, I had never heard of Islam. Now I was drinking sugary tea with Zalabia Bedouins and squatting on a sand drift in Wadi Rum, the Valley of the Moon, less than twenty miles from the Saudi Arabian border.

I returned to England, where I continued to unravel. My first week back in Cambridge, I awoke nearly every night in the street, having run there, shouting, asleep. I developed headaches that lasted for days. My dentist said I was grinding my teeth. My skin broke out so severely that twice perfect strangers stopped me in the street and asked if I was having an allergic reaction. No, I said. I always look like this.

The distance -- physical and mental -- that had been traversed in the last decade nearly stopped my breath, and I wondered if perhaps I had changed too much. All my studying, reading, thinking, traveling, had it transformed me into someone who no longer belonged anywhere? I thought of the girl who, knowing nothing beyond her junkyard and her mountain, had stared at a screen, watching as two planes sailed into strange white pillars. Her classroom was a heap of junk. Her textbooks, slates of scrap. And yet she had something precious that I -- despite all my opportunities, or maybe because of them -- did not.

My mother begged me to find another way. My father said nothing.

One evening, I got into an argument with a friend about something trivial, and before I knew what was happening I had pressed myself into the wall and was hugging my knees to my chest, trying to keep my heart from leaping out of my body. My friend rushed toward me to help and I screamed. It was an hour before I could let her touch me, before I could will myself away from the wall. So that's a panic attack, I thought the next morning.

Soon after, I sent a letter to my father. I'm not proud of that letter. It's full of rage, a fractious child screaming, "I hate you" at a parent. It's filled with words like "thug" and "tyrant," and it goes on for pages, a torrent of frustration and abuse.

That is how I told my parents I was cutting off contact with them. Between insults and fits of temper, I said I needed a year to heal myself; then perhaps I could return to their mad world to try to make sense of it.