The mother and the child came along to the conference at Dagstuhl Castle; it was meant to be a vacation for them. The husband assured her it would be fine. The chef would cook special meals for the child, and there would be a forest, a flower garden, and German bread. “Our boy will love it there.”

The mother didn’t love anything anymore.

While the husband attended talks and panels, the mother and the boy explored marble hallways, a music room with a silent piano, and a game room, where figures stood on a chessboard as if they had grown from the wood. The boy could not walk yet. He crawled so fast he fell on his belly and slid forward.

“Slow down,” the mother called, “Stop!” But the boy didn’t stop.

When it was time for the boy to eat his fruit, the mother took him to the deserted coffee lounge. While the boy, seated in the lone baby chair, was eating a banana, scientists filed in and filled their cup at a large silver coffee urn. The boy observed them. The mother observed them, too. There was something here she needed to know, but she didn’t know what it was yet.

At night, an owl was calling. The scent of mountain streams and freshly cut trees came in through the window. Graduate students played billiards downstairs, and a Polish male professor and two beautiful female students played the piano in the music room.

“Try to sleep,” the husband said out of habit, and the mother pretended she did.

The husband opened his laptop and showed off his code. Personnel offered trays with cheese and drinks. A fat Brit pushed up his shirtsleeves and said he had trained a group of autonomous agents to solve Turing-hard problems, and a professor from India, after taking her time to swallow a mouthful of wine, asked for proof.

Far away, up in the suite, the boy was crying. The mother held him close and walked in circles, humming a song she had made up, four or five monotonous notes trying to convince him that life was good and she was here and he could go to sleep. He screamed louder.

He doesn’t feel I’m here, she thought. He’s alone. He’s scared. I wonder where I’ve gone.

Later, she sat outside on a bench, unnoticed by the scientists spilling out on the brightly lit lawn. A woman had brought an easel and wrote equations on sheets of paper; others drank wine and reclined on garden furniture. Through the window high up in the tower, the mother thought she could hear her son cry. She knew this had happened before, this exact scene: A baby crying in a hidden room in the castle. A mother hiding on this bench, hoping for it to end, powerless to stop it.

The Polish professor and the students gave a concert. Above the music room was the family suite with the boy in his crib, and the mother wondered what the music sounded like up there, whether it was still music at all. They had played music to the boy in the incubator, imagining it comforted him even through the walls of plastic and the whoosh of the machines.

The more beautiful of the two women was also the best piano player. She leaned back, inhaled, and let her fingers connect with the keys. The mother closed her eyes. She could smell the grain of late summer, sunscreen, and exhaust, the air that rushes in and out of open car windows. When she opened her eyes again, one of the painted portraits on the wall was staring at her. The woman in the painting could have been any of the mothers who were walking behind strollers in the park at home: dark hair gathered at her neck, lines around the mouth, eyes made gentle by exhaustion. The woman in the painting looked up at a corner of the ceiling, at the spot where, on the floor above, the boy was sleeping.

“Who is she?” the mother asked her husband. He didn’t know. The next day, she leafed through a book about Dagstuhl Castle she bought at the reception while the boy was crawling up and down the stairs.

The woman was a countess, the former owner of the castle. She used to paint in a studio in the forest. The studio had been built specifically to her wishes. She had sold her paintings and donated the money to the village; the painting in the music room was a self-portrait. The countess had to cope with a big loss, the brochure continued discreetly. She had been forced to give away her illegitimate son. The son had been passed off and raised as the son of a cook.

On the way home, in the roar of the highway and inside the car the smell of cheap coffee and diaper cream, the mother wondered what to do next. The painting had been a clue. She had to make good use of it, if she wanted to understand what was happening to her. Because something was happening—or rather, something was not happening the way it should. Since the arrival of the boy, she, the mother, had been gone without a trace. She was watching herself from afar, powerless. She was a problem she needed to solve. She wondered whether she still could.

The son had been born three months early. He had been lifted from her belly while she had been sedated, no longer than her hand, his eyes hidden behind swollen eyelids, his wrinkled, claw-like fingers closing around the tentacles of the crocheted squid in the incubator. She just had to be there, the doctors told her, just be there and emit the motherly love that would save him. She stopped sleeping then.

The mother pricked up her ears and heard only the engine and the tires and the wind. Carefully, she turned in her seat. A baby was asleep in the car seat. It slept with an opened mouth, fingers stroking invisible kittens. How much he looked like the boy. But he wasn’t the boy. She must have fallen asleep after all, in these first weeks, and the boy was gone. The baby in the car was an imposter. Like she was.

The next morning, the mother opened the door to the boy’s room. The imposter lay at the center of the low bed, wrapped in a blue sleeping bag. He was already awake and clutching at his chest. Her husband didn’t seem to notice anything unusual.

When he was off to work, she rubbed her hands, savoring the rush of caffeine from a second pot of coffee. Being a scientist in a traditionally male field had once made her an attractive mate, and ultimately a mother, so why not do some research on the imposter now? See if she still had it?

Let’s start out with offering the impostor challenging foods and record his reactions.

Stir fry with chili peppers? –> Turns away his head. Sniffs. Samples. Licks his lips.

Piece of trout –> Refuses.

Potato chips –> Suspicious. Plays with bag.

What if she handed him knife and fork? How would he respond to other languages? What about the music of Frank Zappa?

Conclusions: The imposter is convincing. Plausible reactions (crying, protest, surprise), great robustness; ability to adapt to new stimuli and contexts.

A few days in, despite the almost constant caffeine buzz, she was still tired. At night, she lay on the mattress and felt the mites crawl around in her pillow. There was no crying from the imposter-boy, and only snoring from her husband.

One night, her husband woke up. He reached for her hand. “What’s wrong?”

“I lost our boy,” she whispered.

“What?”

“I lost him. Early on. I found out at Dagstuhl.”

He smiled. “He’s getting fast, isn’t he? He’ll walk before his first birthday.”

She clearly had to up her game. He was a scientist, too. Without proof, he would think she was crazy.

The imposter sat on the high chair in the kitchen. He had just eaten a whole sausage and a chocolate bun without complaint, and was dipping his thumb into the crumbs on the table.

The mother put a box of Q-tips, a knife, and her camera on the table. Earlier, she had taken his temperature. She would call former colleagues at the lab and ask them to test the stool samples and the snot.

She opened the imposter’s mouth and shot photos of his teeth and the back of his throat. When she was done, she leaned in closely to examine his eyes, not sure what she expected to see. She lifted a Q-tip, but he pinched his eyes shut and swatted blindly at her hand.

She lifted the knife and grabbed the imposter’s right wrist. He stopped squirming and gave her his full attention. She lifted the knife and pulled the hand closer. He smiled and cooed a question. She wanted to cut. At the last moment, she cut her own hand instead, a deep cut into the soft moon under her thumb. The cut was buzzing rather than hurting, and blood came out, filling her palm. She ran to the sink and held her hand under the cold water until she had the idea the blood flow was slowing. Then she picked up the baby and ran out of the house.

It was hot, summer, the park filled with groups of people sunbathing and playing Frisbee and barbecuing. She was running through clouds of smoke: charred pork, cheap marinade, sangria, and weed. Her lungs hurt. Her hand was sticky again and she tightened her fist to stop the pain. Topless women sprawled on their bellies, topless men stood with their backs turned and peed aggressively in the bushes, and everyone screamed with laughter. Children played football, newborn babies on double-folded quilts waved at the sky, students clinked plastic champagne glasses, and a couple made out under the weeping willow. The mother ran to the water. What happened? She had done something terrible, but she didn’t know what.

“Lady?” A man caught up with her, out of breath. He was young, with a full beard, and wore a tie-dye shirt and gray linen pants. He carried a baby in both arms, cradling its neck with his hand; his hand had a spiderweb tattoo. The baby was the imposter. He was crying.

“Your child,” the man said.

“No, no,” she started. “He’s not my child.”

The man held the baby more tightly. “But you left him at the sand pit.”

“You don’t understand.” The mother had to laugh. “You see, he’s not a child. He’s not a child.”

The hospital room was as white as the creamy ceiling and the stucco angels at Dagstuhl. The mother waited for the call of the owl and the scent of the forest, but the window didn’t open, and the ventilation grid only let in sounds of the city. She had a view of other hospital rooms across the inner courtyard: hundreds of identical beds and off-white walls and night tables with glasses and trays, and sometimes a vase with flowers.

How do you feel? Many people asked her that: the nurse waking her in the morning, the doctor with the tan and the hands-in-pockets pose who seemed to think that none of this was really a big deal, and the psychologist with the spiraling jewelry. Her husband and his mother were now taking care of the imposter. They didn’t ask.

How did she feel? Not ready. Born premature, like her lost boy. At times, she saw him – not much, only the tip of his nose, a hand twitching in a pile of sterilized gauze–and her empty chest cavity seized and tried to close around something.

“I just want to know where he is,” she said. “I want us to be together again.”

“You need to sleep. Please. You’ll kill yourself if you don’t sleep.” The husband looked gray and sad, like in the first months with the premature boy: the mornings when they took over each other’s watch on the neonatal care unit, the baby’s ribcage a broken foam cup sealed in hairy skin, his brain growing inside a soft, sock-protected skull, the apple of knowledge fed by visible blue and red veins.

“It was tough for us,” the husband whispered now. “I should have kept watch over you, too.”

She tried to raise his spirits by telling him about the evidence she had collected.

“The baby who’s living with us now is not our boy. He’s sweet, but he’s an imposter. What an interesting case!”

“It’s okay, you can still like him,” she added when he covered his eyes.

She was walking through a forest in the early morning. Water was running from the sponge of moss under her naked feet, and the mist settled on her face. Her cottage was really a shack: four walls and a roof, not architecturally plausible, but it was the best her imagination could do. She needed more time. Here she could think and soak in hot water. Here she could be alone.

She was scared. One moment, she saw the imposter, and the next moment, she saw the boy. They looked exactly the same. The same gap between the front teeth. The same long lashes, the same pot belly.

She knew she was supposed to see her boy all the time now. Alternatively, she could love the imposter the way she would love her own baby, given another chance. Unless she did either of these things, she would not get out of here.

What if she stayed at the hospital? She could still go to the cottage every night. It would not be a bad life. The music room at the hospital had cheap drums and maracas and one electronic keyboard. Occasionally, a group of patients would gather under the leadership of a therapist and make noise. Something like Hey Jude fading into She’ll be coming ‘round the mountain when she comes.

She and her husband took the imposter from the stroller and sat down on the grass. The imposter crawled towards her and tugged at her pant leg. She smelled him: baby shampoo and cream and a touch of sunscreen. She hadn’t smelled anything in such a long time that it took her a while to recognize it, but eventually she was sure.

“Someone smells delicious,” she said, willing herself to be the kind of mother this world deserves. “Someone is all clean and shiny today.”

The psychologist played with her spiraling jewelry while the mother talked. When it was her turn to speak, she let the jewelry rest on her bosom. “You are terrified,” she said. “This shows me that you are a mother already. You don’t have to look for yourself. You’re right here.”

“But he’s the imposter.”

“Can’t you call him by his name? Just to see what it feels like?”

The mother tried in her mind. “Not yet,” she said.      

“That’s fine.” The psychologist traced the biggest spiral with her fingers. The mother thought she heard a high tone. Maybe this was a clue, too. To the center of the labyrinth, which was also the exit, which was also the entry.

The mother unrolled the mat on the grass, laid a clean diaper next to it, and took the baby wipes and cream from the pockets of the diaper bag. She laid the imposter on the mat on his back, tugged down his pants and rolled up his shirt, and opened the full diaper. The poop was made of different shades of brown and green, not too bad except for the smell. She wrapped the diaper into a tight package and, lifting up the imposter’s legs, cleaned his butt and lower back. The imposter smiled at her in a trance. When his butt was clean, the mother wiped her hands with a new tissue and unfolded the soft new diaper. The imposter lazily pumped his legs.

When her boy had been born, she had used the breast pump day and night. She didn’t eat anything except vending machine cookies and the cups of soup served by the nurses. She heard the pump in her sleep, the little sleep she got. Drop by drop, her collected milk traveled down a tube into the boy’s always surprised “oh” of a mouth. At one point, the doctors told her to stop pumping and to go home. You need to rest. When she stood in the kitchen, she looked at the pictures pinned to the wall, like scenes from the life of a dead person. That person looked like her. That person had been pregnant. She had put on her favorite music, a piano piece, golden and hopeful, like nature promising that all was well, and waited for the music to reach her. She was yearning to cry. Nothing happened. Feeling anything would mean to lie on her back in the hospital bed, her child in trouble, his heartbeat galloping away and fading–or now, next to the incubator, not allowed to pick up the precious little snail and scoop it up against her body. She could not bear feeling any of this. And she didn’t have to. You only have to be here. Your presence will save him. She turned off the music, surprised. She didn’t feel anything. The doctors called her brave.

She fastened the diaper tabs and the imposter kicked his legs with new vigor. She cupped his feet. He kicked harder, his expression serious. Careful. Careful. You think I’m big and strong, but I’m not. The imposter squealed and kicked harder, grunting with each kick. “Careful,” she whispered. “Careful.” They were sitting like this, she kneeling in front of him, enduring his kicks, and finding she could.