I was feeling distinctly uneasy as I sat in my small back kitchen and watched Katya make tea. Opposite me, across the table, a young policeman was asking the usual questions. No, nothing was missing. No sign of any disturbance at all. No damage, nothing.

“Passport, bankbook, post office book…All all right, sir?” He made me feel like somebody’s grandfather.

“Yes, all still here.”

“Do you keep money on the premises?”

“I’d like to, but I never seem to manage it.”

“Well, if you’re really sure, sir.”

He made a note on his pad and looked up at Katya as she approached the table with three mugs of tea balanced on a dinner plate. “I know this must be very disturbing for you both.”

The remark was intended entirely for her, and it made me glance up at her as she turned for the sugar, my attention caught by the young man’s interest. I hadn’t seen much of Katya since she moved in, and I’d never looked at her very carefully before. Now I found her taller and slimmer than I’d thought, attractive in a youthful, slightly angular way. She was wearing black and her hair was dark, too, long and straight, with a fringe that framed her face. Before then the small silver stud in her nose was the only thing I’d ever really taken in. A strange thing, I thought randomly, how little I’d noticed her.

She answered the officer’s questions with a faint accent, but she spoke English naturally, as if she’d grown up with it. Her story was very simple. She had returned a little before twelve and found the glass in the door broken. She’d called the police immediately and waited on the stairs. She hadn’t touched anything. She had lived here two months. She had never seen anyone acting suspiciously near the front door. She was from Sweden and was studying for a master’s degree in history.

At this point something bleeped in the officer’s pocket and he began to put away his notebook.

“There’s nothing much else I can do here, sir,” he told me neutrally. “Probably just kids. But I’m afraid you’ll need to take steps to make these premises more secure. With a front door like that, it’s only surprising it didn’t happen sooner.”

I got up to show him out, but Katya rose, too, and as she was nearer the door, I let them go with a nod. From the hallway I could hear a voice lowered confidentially.

“If you need me again, miss, here’s the number to call. Any time. Just pick up the phone…”

Then the front door shut and Katya returned to the kitchen and the chair opposite me. The downstairs kitchen was my kitchen—Katya had her own—and it felt strange for us to be alone together there. Nevertheless, it was a good place to sit—an aging boiler kept it warm at unlikely times and a quirk of the ventilation meant it always smelled of coffee from the offices next door. Even tonight it felt immune from the sense of intrusion that hung in the hallway and the rooms beyond. The room was mostly filled with an old wooden table, and it was there that we sat, in the soft yellow light, neither of us speaking for a moment. When I looked up from my tea, she was watching me from under her fringe of hair.

“Is it true?” she asked. “Is there really nothing missing? You didn’t seem sure.”

I paused before I replied, afraid of making a fool of myself.

“No, nothing missing. I just feel unsettled.”

Katya nodded. “It’s never nice to think of someone poking around. But at least they didn’t take anything.”

That was what was worrying me. I could have understood theft.

“There’s something I noticed,” I told her. “Something a bit odd.”

She was looking at me carefully. “What sort of thing?”

I didn’t attempt to explain until she’d followed me upstairs and we were standing side by side facing the bookshelves that covered one wall of my bedroom.

“Have you ever seen any of those black-and-white films where the detective comes back to find his office has been ransacked? Well, this is exactly the opposite.”

She looked alarmed and slowly shook her head, not understanding. I wasn’t quite sure how to explain.

“Here, run your finger along my desk. What happens?”

She picked up her finger and blew on it.

“Nothing happens. Just dust.”

“Exactly. Now do the same on the bookshelves.”

She didn’t need to.

“Nothing. They’ve been dusted.”

“Take a look around. Do I look like a man who dusts?”

It wasn’t hard to see what I meant. Everything in the room that wasn’t in daily use was covered with a thin layer of dust—the chairs, the wooden chest, even the photograph by my bed. But the bookshelves were immaculate, beautifully and carefully wiped clean.

Someone had dusted my bookshelves.

It was too absurd to really believe. My first thought on finding it had been that something must be missing, that perhaps someone had wiped extravagantly for fingerprints after a theft. But there were no gaps between the crammed books to suggest an absence, and I knew the contents of those shelves so well I could almost recite them. And besides, there was nothing worth stealing. No book in the whole collection of any real value.

To my surprise, Katya began to giggle.

“So,” she began, trying to restrain herself, “you think someone would break in to do your cleaning? I mean, it isn’t that messy.”

It was about then that I found myself liking her. I think it was her laughter, the way she kept things in proportion. The break-in was confusing, and the conversation with Anderson was still on my mind. I needed someone to listen while I tried to manufacture a little cosmos out of the chaos. So that she wouldn’t go away, I cleared her a seat and began to tell her about my evening at the Mecklenburg Hotel. But to make sense of that, I found I had to tell her about the book I’d never written, the ultimate book about extinct birds. A book that was going to make each one, in a little way, live again. I told her about the discoveries I’d made in obscure collections and the unknown drawings I’d found in the papers of dead travelers, and then about some of the birds themselves: the Stephen Island wren, entirely wiped out by a single domestic cat; the spectacled cormorant, eaten to the brink of extinction by Arctic explorers and finished off by a fleet of Russian whalers in the course of an afternoon.

Katya listened with her elbows on her knees and her hands around the tea she’d brought up with her. She didn’t seem bored, and she prompted me when I hesitated. When her tea was finished, I fetched two glasses and a bottle of Polish vodka from the freezer. When I went to close the curtains, the street outside lay in darkness, the night gathered thickly beyond the reach of the streetlamps. It had started to rain again.

“Why did you never finish it?” she asked as I filled the glasses.

It was hard to explain. I picked up the bottle and put it between us. It was still four-fifths full.

“Look,” I said, pointing to the empty fifth at the top of the bottle. “When I set out I thought all I had to do was describe the gap here.” She looked at the empty part and nodded.

“But do you see? After three years I was farther from finishing than when I started. The level in the bottle keeps falling, and the rate it drops gets faster and faster. Each year there are more and more species on the brink, more empty space about to appear in the bottle. Sometimes they even discover new species, but they go straight onto the endangered lists, too. And then there are the empty bottles we don’t even know about, the birds extinct before we even noticed them. One day I suddenly realized that I’d never catch up. There’s never going to be a definitive work about extinct birds. All we can do is record the handful we happen to know about. The rest are gone forever.”

She pursed her lips. “I hadn’t thought of it like that. But what has this got to do with the dust on your shelves?”

So I told her about my meeting with Anderson and his plan to hunt for the remains of the rarest bird in the world. The room got warmer as we talked. Every now and then Katya sipped at her drink, wrinkling her nose slightly at every sip. The idea of the lost specimen, the evidence of a whole vanished species, seemed to fascinate her.

“I can see why it’s valuable,” she nodded as I tried to explain the DNA collectors, “though fifty thousand dollars seems a huge amount for a dead bird.”

I shrugged. “That depends on how you look at it. A great auk would be worth a fortune, and there are about twenty of them. And if you came across a preserved dodo, you’d be able to retire for life. Seriously. You see, there’s no such thing as a preserved dodo skin, only bones and beaks and things. So perhaps something genuinely unique does have a value.”

Katya looked unconvinced.

“It’s got another sort of value, too,” I went on. “You see, for a species to officially exist, there has to be something called a type. That’s a sample specimen, one that’s held to be typical of the species. Without a specimen, there’s no type, and without a type, science doesn’t really recognize that something exists. So if we’re going to be strictly scientific about it, the Ulieta bird isn’t even extinct. It just never happened. There’s no physical evidence, no bones, no feathers, nothing. Just a drawing, a few lines of writing, and one lost bird.”

Katya nodded slowly. “But where do your books fit in?”

I looked at them.

“I’ve absolutely no idea. None of them is very special. Besides, if there was a clue somewhere, wouldn’t whoever it was have taken it away?”

Katya turned and studied the wall of books thoughtfully. “Perhaps they did. Perhaps there’s a page torn out of one of them. You ought to check.”

“Let’s see, a thousand books at three hundred pages per book…”

She turned back to me then and we both laughed, appalled at the thought of going through them.

“Perhaps another day,” she said.

“Perhaps another month.”

We stayed there drinking until the bottle was two-thirds empty. As we talked, I began to see her differently. Her face lit up when she spoke, and her vitality was infectious. Our conversation went from birds to history, and we rambled happily about the way things in the past come to be recorded, about the way Time takes things away from us if we don’t fight to keep them. It was common ground of sorts.

“My father teaches history at the university in Stockholm,” she told me. “He used to be a real historian, the sort who went off and found things out. When he met my mother he was going to be the most brilliant historian in Sweden. Now he’s never out of restaurants and TV studios and he writes the books the publishers tell him to write. He’s too busy doing interviews to care anymore.” She shrugged. “We don’t get on. That’s why I came to England. I want to do it for myself.”

“And is that why you don’t phone your mother?”

She paused, her face a half frown. “My father walked out on her when I was a teenager. She didn’t even fight. Not even for my sake. She just let him go.”

It was too harsh a reason to reason against. She reached out and ran her finger down the spine of one of the volumes. We’d been talking for a long time now. It made questions easier. Now it was her turn.

“Why didn’t you take the money you were offered?” she asked.

“If I wanted money, I wouldn’t be doing what I do. Besides, there was something about Anderson. I didn’t like his suit.”

At that Katya spluttered on her vodka and began to laugh again and we were both still laughing as we swept up the glass in the hall and tried to seal up the broken windows with tacks and plastic bags.

Finally we stood by the semi-repaired door, facing each other, both smiling. Despite the break-in I felt oddly lighthearted.

“So many lost things,” she mused, her voice growing a little more serious. “Why don’t you go and look for it?”

I shook my head slowly. “I wouldn’t know where to start. The trail went cold two hundred years ago. And, besides, Anderson is a professional. He knows what he’s doing.”

Those words ran through my mind again in the early hours of the morning when I finally reached my bed. It was an impossible task, surely. But Anderson’s confidence disturbed me. Could he be right? Could it really be that the bird had survived in some unknown collection, untouched since the days of Cook and Joseph Banks? I tried to put the thought away, tried to remind myself that my life had moved on. But Anderson knew better than that. He understood that I’d left something unfinished, that I’d never made a find like the one he was intending. The bird of Ulieta. The lost bird. It would be the most remarkable find of all.

I knew I should sleep, but my mind kept turning, and as the night began to change into the gray light of a winter dawn I realized I had one small, faint hope, something I knew that Anderson couldn’t possibly know. A decision made, I felt able to swing myself into bed, and it was then I noticed that the photograph on my bedside table had fallen over, as if someone had knocked against the table. I stood it up carefully and looked at it for a moment. When I turned out the light, the room didn’t go dark.

THREE DAYS later she returned to the clearing where Banks had watched her sketch. It was a day to savor. The sky was an unblemished blue and the sun was hot on her skin. She found the fallen branch where she had been seated previously and fixed her attention on the ground before her. Without any great preparation she began to draw. As she worked the silence of the woods turned to small noises—the water in the stream, the darting of unseen birds.

She had learned that only when in the woods could she be the person she knew herself to be. As her father’s daughter she had needed to protect herself from the world she lived in. Here that world was no more than a fleeting odor on the breeze.

She didn’t hear him approach. The sound of his voice, sudden in the quietness, made her start and turn.

“Lichen pulmonarius,” he said simply, and her eyes went to the place on the edge of the clearing where he stood. “The name of the lichen on the trees in Slipper Wood,” he added.

With that, he stepped forward into the sunlight and she saw he was smiling. Behind him the trees were deep green. Later she always remembered that moment, that smile.

“That is what you were looking at.” His voice betrayed no doubt. “It grows only on the trees you were examining and on no others.”

He stood before her, his smile both a greeting and a challenge. His shirt was open at the neck, his hair unkempt. In one hand he swung a leather collecting bag. She had never seen anyone so alive.

“I don’t know its Latin name,” she replied. “They call it tree lungwort. It’s different from the lichens around it. But you’re wrong to believe it grows nowhere else in these woods.”

“I am?” He placed his bag at his feet and looked at her again. She had remained seated, looking back at him. If she had flushed on his arrival there was no sign of it now. Yet he felt again that in the moment before his greeting he had glimpsed a person different from the one now before him. Now only the green eyes remained the same.

“I was sure I had examined each tree most particularly,” he said.

As he spoke he was wondering about that other person, the young girl alone, drawing so avidly. Later, in lands where people hadn’t learned to hide their joy at living, he was to think of her again. But for now he was aware only that he was being studied by a cool and thoughtful face.

“It grows on just those twelve trees in Slipper Wood,” she stated. “But you’ve certainly seen it elsewhere. You will find traces of it on nearly every tree in your home park.”

He shook his head in response, the naturalist in him reasserting itself.

“No, I had not observed it. Or rather, if I had, I had not noted it. Do you believe what they say, that it is a cure for sickness of the lungs?”

He began to feel embarrassed standing before her, as if his presence was an intrusion. And she was looking at him from where she sat with clear, calm eyes that neither welcomed him nor made him wish to depart.

“No, that’s surely not true,” she said, her gaze turning for the moment to the trees all around them. “They say so because of its appearance, like the texture of a lung. But that is coincidence, surely? I cannot believe that Providence felt it necessary to illustrate its workings in such literal ways.”

“I confess I am surprised. And overjoyed. I had no idea Revesby contained a fellow natural philosopher.”

Embarrassed at towering over her, yet unable to sit without being invited to do so, he instead sank to his haunches as though he wished to study something on the ground in front of him. It was, he knew, an assumption of informality.

To which she responded by rising to her feet and preparing to depart.

“I am hardly that, Mr. Banks. I have no books to study, and my tutor is no longer able to instruct me.”

“Your tutor?” he asked, rising hurriedly, caught off balance.

“My father, sir.”

“Of course. My apologies. I did not mean to pry.”

“And yet your presence here would suggest the opposite.”

It was not said coldly but with an air of detachment that made him step backwards.

“My apologies, madam. I had not realized my presence here was objectionable to you.” And as he spoke she saw the sunlight go out of his face. The sight stopped her even as she began to move, though she had thought herself safe. She could feel it even then. She knew she should turn away and return to the village, past the low houses with their gazes averted as she passed. But she had not intended to wound, only to safeguard her own retreat. Around her the summer morning was still sweet. So, although she began to understand the risk, she turned back to him and met his eye.

“I am not used to company, Mr. Banks. I have known these woods since I was a girl and I was taught to notice what I saw around me. It would be a great luxury to talk about these things. But today I have this drawing to complete. Soon this flower’s season will have passed and my opportunity will be lost.”

He hesitated, concerned that her more curt response was the true one.

“Of course,” he responded. “It was selfish of me to interrupt your work. Please be seated again,” and he gestured at the fallen branch. “There are few here that share my interests.”

As she seated herself she took care that her dress fell properly to the ground. When he spoke again she had opened her book and was turning to the page of her unfinished drawing.

“I shall bid you farewell and leave you to your work,” he began.

But his sentence trailed away and she sensed no motion to withdraw. Instead she felt him move forward. When she looked up she saw his eyes fixed intently on the drawing in her hand, and the expression on his face sent a flash of joy to her heart.

THAT DAY she stayed out late, until the light in the woods began to thicken into dusk. Then she returned home slowly along the fringes of the fields with the stars already showing above the trees. On reaching the house at the edge of the village, she paused with the door open, then let it close softly behind her, knowing that in the whole village on such an evening her door was the only one shut against the night air. Inside the house the shutters were fastened, trapping the heat of the day, and a candle burned in the dark. It was suffocatingly hot. She put her drawing book down on the bare table in front of her and listened. Upstairs her father was dying.

She stood listening for nearly a minute. She could hear the low whispering of Martha, the nurse, as she cleaned him. She had had so many months of practice now that it didn’t take her long; even turning him barely made a sound. Beneath it all, regular and slow, his breath counted away the days and the hours. Finally, content from her place in the hallway that all was unchanged, she went to wash herself. Then, with her hair still damp and loose, she went upstairs.

Martha greeted her with a nod and a smile and briefly the two sat in silence on either side of the sleeping man.

“Thank you, Martha,” she said eventually. “You can leave me for a while. You must get yourself some supper.”

The older woman began to stir herself, then paused. “Mr. Ponsonby called again today, miss.”

The two exchanged a look.

“Then it’s fortunate I was not at home, Martha.”

After another silence, Martha spoke again.

“He has not asked for rent these twelve months, miss.”

“I know he has not.” She lowered her head. “There is nothing we can do about that.”

She might have said more, but she was eager to be left alone that evening. When Martha had gone downstairs, she sat for a little, listening to her father’s breathing. Sometimes at night its steady rise and fall crept into her dreams like the sighing of the sea. On other nights it fell quiet and then she would go to him and lean close, anxious, like a mother over a sleeping infant.

She had been upstairs sleeping that night they brought him home. At first she thought it was drink that affected him and she had been ashamed. Then she saw his hair was matted with blood and they told her how he had been found. He had been drunk, they said, and had interrupted the Ponsonbys at dinner. He’d been thrown out by the servants there and had wandered into the darkness. The men who found him had been returning horses to the stables at High-wold when they noticed him in a ditch, his head hard down on a stone.

She hurried them out as soon as they had carried him upstairs, hating for them to see him so helpless. That night she tended him, mopping at the wound, an ache of anxiety deep in her stomach. The wound seemed clean. There was not much blood. Yet he would not stir. She tried to force a little brandy between his lips and then waited through the night for him to open his eyes.

The doctor came the next day, even though she had not sent for him. He was a good man: there were few who would come willingly to their door.

“You must try to feed him,” he said. “Anything he can be made to swallow without choking him. You need him to keep up his strength.”

The days that followed were suffused with half-light, as the full daylight disturbed him. She found he would swallow what she could force between his lips, but at other times of day he lay inert, unconscious of her touch. After a week Dr. Taylor returned and brought with him Martha, a nurse. She was a woman from the next village who had once nursed his own children and at his request she was willing to accept work in the house of a sinner and a heathen.

“You must understand,” he said when Martha had gone downstairs to store away her things, “that the longer he sleeps, the less likely his waking.” She nodded at that but he could see she hadn’t heard. It was a lesson he would have to repeat.

“Doctor,” she said when he came to leave, “my father has debts. I have nothing to pay the nurse.”

He looked at the troubled green eyes.

“Martha will come to me for her wages,” he told her.

“But I cannot…”

She looked up at him, wordlessly asking him to understand. But he was a study of concentration fastening his glove, and he paused only to add that he would call again when he could.

The day of his next visit he found her changed. She was neatly dressed and she did not smile as she greeted him. As she led him upstairs she explained there had been no change, that her father was still unaware of the world around him. But he could see for himself a change in the man’s face, the gray pallor of his skin and a reshaping of his cheeks, as though he was inching away from life. He knew she had seen it, too, knew by the way she touched the patient as she tended him, softly now, like a caress. He had learned to recognize the ways people begin to say good-bye.

“Doctor,” she whispered, “it is possible that my father may not recover, is it not?”

“I fear that is possible,” he replied, wishing she had a mother to place an arm around her. “The wound to his head is more profound than was apparent to the eye.”

“Will it be long?” Her voice was smaller than he had ever heard it.

“I cannot say. I have known men in his state to survive for many weeks. Recover too, sometimes. You must tend him well and keep him comfortable.”

“I shall,” she said. “And then…” But neither of them cared to complete the sentence, and after only a few words more the doctor withdrew.

She was already used to walking alone. The day after the doctor’s visit she stood on the edge of the wood and let the sun warm her face as if its touch might smooth away every thought. She felt the roughness of the grass on her fingertips and let it fill her mind. She made herself memorize the pattern of leaves on the forest floor and the way the saplings turned and twisted toward the light. And to keep these things forever, to have them fill the emptiness inside her, she took up her pencil and drew.