There really was a lake in Blind Lake, Tessa Hauser had learned. She thought about that as she walked home from school, following her own long shadow down the sparkling white sidewalk.

Blind Lake — the lake, not the town — was a muddy swamp between two low hills, full of cattails and wild frogs and snapping turtles, herons and Canada geese and stagnant green water. Mr. Fleischer had told the class about it. It was called a lake but it was actually a wetland, ancient water trapped in the stony, porous land.

So Blind Lake, the lake, wasn’t really a lake. Tess thought that made a certain kind of sense, because Blind-Lake-the-town wasn’t really a town, either. It was a National Laboratory, built here in its entirety, like a movie set, by the Department of Energy. That’s why the houses and shops and office buildings were so sparse and so new and why they began and ended so abruptly in a vast and empty land.

Tess walked by herself. She was eleven years old and she hadn’t made any friends at school yet, though Edie Jerundt (whom the other children called Edie Grunt) at least spoke to her once in a while. But Edie walked the other way home, toward the mallway and the administrative buildings; the tall cooling towers of Eyeball Alley, far away to the west, were Tessa’s landmark. Tess — when she was with her father, at least, which was one week out of four — lived in one of a row of pastel-colored town houses pressed up one against the next like soldiers at attention. Her mother’s house, though even farther west, was almost identical.

She had stayed twenty minutes late at school, helping Mr. Fleischer clean the boards. Mr. Fleischer, a man with a white-brown beard and a bald head, had asked her a lot of questions about herself — what she did when she was home, how she got along with her parents, whether she liked school. Tess had answered dutifully but unenthusiastically, and after a while Mr. Fleischer had frowned and stopped asking. Which was perfectly okay with her.

Did she like school? It was too early to tell. School had hardly started. The weather wasn’t even cool yet, though the wind that brushed the sidewalk and flapped her skirt had a touch of autumn in it. You couldn’t tell about school, Tess thought, until at least Halloween, and Halloween was still a couple of weeks away. By then you knew how it would be — for better or worse.

She didn’t even know if she liked Blind Lake, the town-not-a-town near the lake-not-a-lake. Crossbank had been better, in some ways. More trees. Autumn colors. Snow on the hills in winter. Her mother had said there would be snow here, too, and plenty of it, and maybe this time she would make friends to go sledding with. But the hills seemed too low and gentle for proper sledding. Trees were sparse here, mostly saplings planted around the science buildings and the shopping concourse. Like trees imperfectly wished-for, Tess thought. She passed some of these on the lawns of the town houses: trees so new they were still staked to the earth, still trying to take root.

She came to her father’s small house and saw that his car wasn’t in the driveway. He wasn’t home yet. That was unusual but not unheard-of. Tess used her own key to let herself inside. The house was ruthlessly tidy and the furniture still smelled new, welcoming but somehow unfamiliar. She went to the narrow, gleaming kitchen and poured herself a glass of orange juice from the refrigerator. Some of the juice spilled over the lip of the glass. Tess thought about her father, then took a paper towel and wiped the tiled counter clean. She deposited the balled-up evidence in the bin under the sink.

She carried her drink and a napkin into the living room, stretched out on the sofa, and whispered “Video” to turn on the entertainment panel. But there was nothing except static on any of the cartoon channels. The house had saved a couple of programs for her from yesterday, but they were dull ones — King Koala, The Unbelievable Baxters — and she wasn’t in the mood. She guessed there must be something wrong with the satellite, because there was nothing else to see, either… only the closed-circuit feed from the downloads, Lobster City nighttime, the Subject motionless and probably asleep under a naked electric light.

Her phone buzzed deep in her schoolbag on the floor at her feet, and Tess sat up abruptly. A mouthful of orange juice went down the wrong way. She fumbled the phone out and answered, hoarsely.

“Tessa, is that you?”

Her father.

She nodded, which was useless, then said, “Yes.”

“Everything okay?”

She assured him she was fine. Daddy always wanted to know whether she was okay. Some days he asked more than once. To Tess it always sounded like: What’s the matter with you? Is something wrong? She never had an answer for that.

“I’m working late tonight,” he said. “I can’t take you to Mom’s. You’ll have to phone her and have her pick you up.”

Tonight was the night she changed over to her mother’s house. Tess had a room in each house. A small, neat one at Daddy’s. A big messy one at her mother’s. She would have to pack her school stuff for the change. “Can’t you call her?”

“It’s better if you do it, sweetie.”

She nodded again; then said, “All right.”

“Love you.”

“You too.”

“Keep your chin up.”

“What?”

“I’ll call you every day, Tess.”

“Okay,” Tess said.

“Don’t forget to call your mother.”

“I won’t.”

Dutiful, and undistracted by the blank video panel, Tess said good-bye, then whispered “Mom” at the phone. There was an interlude of insect sounds, then her mother picked up.

“Daddy says you have to come get me.”

“He does, huh? Well — are you at his place?”

Tess liked the sound of her mother’s voice even over the phone. If her father’s voice was distant thunder, her mother’s was summer rain — soothing, even when it was sad.

“He’s working late,” Tess explained.

“According to the agreement he’s supposed to bring you. I have work of my own to finish up.”

“I guess I can walk,” Tess said, though she made no effort to conceal her disappointment. It would take her a good half hour to walk to her mom’s place, past the coffee shop and the teenagers who gathered there and who had taken to calling her Spaz because of the way she jerked her head to avoid their eyes.

“No,” her mother said, “it’s getting late… Just have your stuff together. I’ll be there in, oh, I guess twenty minutes or so. ‘Kay?”

“Okay.”

“Maybe we’ll get takeout on the way home.”

“Great.”

After she deposited the phone back in her schoolbag, Tess made sure she had all the things she needed to bring to Mom’s: her notebooks and texts, of course, but also her favorite shirts and blouses, her plush monkey, her plug-in library, her personal night-light. That didn’t take long. Then, restless, she put her stuff in the foyer and went out back to watch the sunset.

The nice thing about her Dad’s place was the view from the yard. It wasn’t a spectacular view, no mountains or valleys or anything as dramatic as that, but it looked out over a long stretch of undeveloped meadowland sloping toward the road into Constance. The sky seemed immensely large from here, free of any borders except the fence that encircled Blind Lake. Birds lived in the high grass beyond the neatly trimmed lawn, and sometimes they rose up into the huge clean sky in flocks. Tess didn’t know what kind of birds they were — she didn’t have a name for them. They were many and small and brown, and when they folded their wings they flew like darts.

The only man-made things Tess could see from her father’s backyard (as long as she faced away from the mechanical line of the adjoining town houses) were the fence, the road that led across the rolling hills to Constance, and the guardhouse at the gate. She watched a bus driving away from Blind Lake, one of the buses that carried day workers home to their houses far away. In the fading dusk the windows of the bus were warm with yellow light.