“Something going on, ” she told Suze when she got back to the apartment. They sat on the back steps, a bag of peanuts between them, watching black clouds move steadily in from the west, blotting out the blue summer sky.

“Another thunderstorm, ” Suze said. She opened the screen door and leaned in to look at the kitchen clock. “It’s eleven thirty. Same time as yesterday. I wonder why that is?”

“I don’t know, but I hope there’s hail again. That was amazing. ”

“Only because you were inside. I got caught by the post office, and it hurt. I’m surprised I’m not black and blue. ” Suze held out her arm, which showed no sign of hailstone damage.

“Besides the thunderstorm, ” Dewey continued. “Do you think the MPs are going to the desert? Is it more important to guard than the Hill?”

“That Trinity place is, ” Suze said. She opened a peanut with her thumbnail. “My dad’s down there all the time now. He takes a bag of sandwiches and a thermos of coffee and doesn’t come back for two or three days. ”

Dewey nodded. They were going to test the gadget. It was an open secret. No one was supposed to know anything, officially, but in private, it was all anyone had talked about for weeks.

Dewey hates the war as much as anyone. If not for the war, she and Papa would still be living in their cozy apartment across from Harvard Square. He would never have gone to Chicago or New Mexico. Or Washington. The war has taken everything away, but now it is her only hope. Mrs. Gordon has said that she can stay with them for the duration, and that is only as long as the war.

When the war ends, everything will change again. The Gordons will leave, and Dewey will have to go somewhere else. To a home, to an orphanage. Every day she walks around the Hill, relishing her freedom while she has it. Every day she crosses her fingers that they will not test the gadget. Not yet. She cannot wish for it to fail—that would mean Papa had failed—and she does not want any more soldiers to die. But she does not want the war to end.

This is a secret she can tell no one. Not even Suze, late at night, when they talk in the darkness. It is unpatriotic, it is treason. Dewey hides her thoughts behind the pages of the boys’ war comics, full of flags and blood and bravery.

Mrs. Gordon came home late Saturday afternoon, her hair in damp tendrils, her cheeks red with excitement.

Dewey looked up from Air Aces. “It’s happening, isn’t it?” she asked quietly.

“Hmmph. And they call this a top secret project. ” Mrs. Gordon put her bag of groceries down on the counter. “Not inside the fence, that’s for sure. The rumor mill down at the Commissary is buzzing at a fever pitch. ” She looked out the window at the storm clouds massing once again in the west. “But yes, if the weather cooperates, it looks like tomorrow’s the day. ”

Dewey felt her stomach tense. “Are you going down there?”

“Nope. ” Mrs. Gordon shook her head. “They offered me a seat on the bus, and it’s tempting, but I’m going to stay here with you girls. Phil’s going down. He can bring back the skinny. ” She pulled a large white paper-wrapped bundle out of the bag.

“Pot roast tonight, ” she said. “He’ll need a hearty meal—Lord knows when he’ll get a chance to sit and eat again—and it’ll make good sandwiches for tomorrow. ” She pulled a bunch of carrots out of the bag and handed Dewey the vegetable peeler. “If you’ll scrape these, I can do the potatoes with a paring knife. ”

“Okay. ” Dewey tore the lacy green leaves off the tops of the carrots, then shaved long thin orange curls into the wastebasket. She worked methodically, carefully. She felt like she was preparing her last meal.

Dewey sat on her bed reading Air Aces’ “Raiders of the Purple Dawn, ” her fingers crossed behind the pages, hoping the storm would continue and the test would be canceled.

But the rain stopped. Mrs. Gordon made a stack of thick beef sandwiches wrapped in waxed paper and rousted Dewey and Suze. By 4:00 they were walking with their neighbors down to the Tech Area.

It seemed as if everyone on the Hill was there, holding a thermos of coffee or a sack lunch or a bottle of suntan lotion. Three buses had been painted so they weren’t army green anymore. Dewey wasn’t sure why they’d bothered, since the buses were going to be escorted south by three official sedans and a canvas-topped army truck full of equipment—jerry cans of water and gas, radios, big coils of wire, and a box with dozens of welders’ goggles.

When everything was loaded, Dr. Gordon kissed Mrs. Gordon and hugged Suze and then, as an afterthought, gave Dewey a little salute from the door of the bus, and disappeared inside. At half past five the convoy headed out the east gate, and it began to drizzle again.

“I want you girls in bed early, ” Mrs. Gordon said as they walked home, ducking under overhangs and into doorways every few minutes to avoid the brief downpours. “As soon as it’s dark. ”

“How come?” Suze asked. “Have I been bad or something?”

“Not that I know of—” Mrs. Gordon cocked an eyebrow and looked at Suze, who shook her head.

“Then why?” asked Dewey.

“Because unless it’s raining cats and dogs, we’re going to get up early and have a little picnic. ”

“A breakfast picnic?” Suze sounded skeptical.

“Earlier than that, ” Mrs. Gordon said. “A middle-of-the-night picnic. ”

Suze frowned. “That’s kind of strange, isn’t it?”

“We live in very strange times, my dear. ” Mrs. Gordon was smiling.

She thought about the gadget and the buses full of men driving across the desert. She turned over, scrunched up her pillow, and wondered if the air really could catch on fire. Suze was snoring lightly, because her nose was stuffed up, and the noise seemed to fill the small room. Dewey scooted the blanket around with her feet, tried sleeping on her side, then on her stomach, and worried about how many more nights she would sleep in this bed at all.

Finally she put on her glasses and got up to get a glass of milk. Sometimes that helped.

The apartment was dark except for the light over the kitchen table. Mrs. Gordon wore the same clothes she’d had on earlier. She sat with her feet up on a chair, a cup of coffee by her elbow, a cigarette in the ashtray. Her reading glasses lay on top of an open copy of The Saturday Evening Post.

“Can’t sleep, Dewey?”

Dewey shook her head.

“I’m not surprised. It’s pretty exciting. I knew I wouldn’t sleep a wink, so I just stayed up. ” She looked at the clock. “It’s almost two. I was going to wake you in an hour anyway. Why don’t you have a cup of Ovaltine and keep me company?”

“Okay. ” Dewey sat down.

“I filled up the thermos—you girls are still a bit young for coffee—but there’s a little left in the pan. ” She tilted the saucepan over a thick china mug and put the Ovaltine down on the table. “It ought to be cool enough to drink. I took it off the burner a while ago. ”

Dewey took a small experimental sip. It was barely warm. She took a deeper drink. “Where are we going?” she asked.

“Out to the south mesa, where it overlooks the Hill road. Some of the guys have been out there all night, but I figure we might as well be comfortable until it’s time. The show—if there’s going to be a show in this weather—is supposed to be at four. ”

“The gadget?”

“We hope so. ”

Dewey sipped her Ovaltine and thought for a minute. “But isn’t the Trinity place like three hundred miles from here?”

“Not quite. More like two-twenty. ”

“But still, we won’t be able to see anything. I mean, the earth curves too much, doesn’t it?”

“Ah, my practical little scientist. ” Mrs. Gordon smiled. “A good question. Yes, it does. For most normal phenomena. But if everyone’s calculations are correct, we’ll have visual confirmation, even way up here. ”

She saw Dewey frowning, biting her lip, and patted her hand. “Still worried about the atmosphere igniting?” she asked gently.

Dewey nodded. It was one of the things she was worried about.

“Well, as I said before, I don’t think it will. I really don’t. But you’re in good company. There’s half a dozen Nobel laureates out there right now wondering the same thing. A lot of questions are going to get answered in the next couple of hours. ”

Not all of them, Dewey thought.

They sat in the kitchen for a few minutes staring out into the darkness. Mrs. Gordon smoked a cigarette, Dewey finished her Ovaltine. At quarter of three, Mrs. Gordon stood up and stretched. “Why don’t you go get your clothes. Grab a sweater. It may be windy. You can change in the bathroom while I try to wake Sleeping Beauty. That could take a while. ”

By the time Dewey was dressed, Suze was up, more or less. She stood in her pajamas staring blearily into her dresser drawer as if she had never seen underwear before. Dewey took a Captain Marvel into the kitchen to wait.

They trooped down the wooden stairs in complete darkness, carrying blankets, thermoses, and a paper sack of sandwiches and cookies out to the car. The eastern sky was cloudy, but directly above, the night sky seemed to have a million stars, with the haze of the Milky Way arcing across the inky dome.

No streetlights on the Hill. Rectangular patches of light spilled onto the dirt road from a few apartment windows, and when they were past the Lodge, Mrs. Gordon drove with her low beams on. All Dewey could see were the trunks of trees, streaks of bright water in the road, and the occasional green-gold glow from a foraging raccoon’s eyes. Everything else was darkness. They drove in silence for ten or fifteen minutes, Dewey figured, Suze half asleep against the passenger-side window, Mrs. Gordon drumming her fingers softly on the steering wheel. Then she pulled off the road and turned off the engine. “We can walk from here, ” she said.

Dewey opened the car door and was glad she’d brought a sweater. The air was cool and smelled clean, as if the rain had washed the mesa, leaving only the scents of piñon and damp earth.

Mrs. Gordon had a big silver flashlight and walked ahead, shining it on the path, a faint trace slightly more compressed with footprints than the surrounding gravelly sand. Up ahead Dewey could see little pools of light from other flashlights and the smaller metallic glints of eyeglasses and wristwatches. As her eyes adjusted to the dark, she made out a cluster of people, fifteen or twenty rounded shapes against the flat angles of the mesa rocks.

Friends called out greetings, and Mrs. Gordon laid the plaid blanket down in a clear space next to them. People were talking in small groups, some subdued, some excited, and every few minutes a circle of light winked on and off as someone checked his wristwatch for the time.

“Any word, Nance?” Mrs. Gordon asked a woman on her left. Suze lay down and put her head in her mother’s lap.

“Still storming, but the meteorology guys say it’ll clear within the hour. Zero’s been moved back to five thirty. ”

Dewey heard a crackle of static. “Is there a radio here?”

A man two blankets over—too far for Dewey to see his face—said, “Two of the SEDs brought a shortwave. We were getting transmissions from the observation planes over the site, but the weather’s grounded all but one. ”

“Can I go see?” Dewey asked Mrs. Gordon.

“Sure. Take the flashlight. But point it down and keep your hand over it so no one loses their night vision, okay?”

Dewey nodded and followed the sound of the radio, stepping carefully between the blankets. It was like being on a beach that had no ocean. She didn’t need the flashlight. Her eyes had adjusted enough to make out the lighter shapes of shirts and hands and sandwiches.

It was a great radio, a Zenith Trans-Oceanic. The two men operating it seemed surprised when she asked a question about its reception—probably because she was a girl. But they answered it, and Dewey had a very interesting conversation with them about the wave magnet antenna until another transmission came through and the engineers had to go back to work.

Dewey sat on the hard-packed dirt a few feet away, listening to the crackling report from the faraway pilot and looking out over the edge of the world. It was too dark to see much difference between sky and land, except the sharp edges below which the star-speckled black was solid. A thousand feet down, on an invisible road, a single pair of headlights as tiny as pinpoints moved slowly across the featureless darkness.

When she began to feel stiff from sitting on the damp ground, Dewey made her way back to their blanket, Mrs. Gordon’s face recognizable in the red glow of her cigarette’s tip. She drank a cup of Ovaltine, warm in the cool night air, and ate half a pot-roast sandwich. To her left, a few pale streaks were beginning to appear in the eastern sky when one of the radio men shouted, “This is it!”

Dewey stared out into the darkness, not looking at anything, her fists clenched in excitement and fear.

And suddenly there was a bright light, as bright as the sun. It lit up the faces of the people and the leaves of the trees. Dewey could see the colors and patterns of blankets and shirts that had been indistinct grays a second before, as if it were instantly morning, as if the sun had risen in the south, just this once.

Time stood still for a moment, and then the light faded. A minute later she heard—and felt—a long, low rumble, like distant, alien thunder. It faded as well, and after a moment’s pause, everyone on the mesa stood and began hugging each other. Conversations grew louder, happier, as their silent vigil became a party. Several men pulled out bottles and silver flasks, which quickly made a circuit of the group. One of the radio men did a spirited Irish jig.

Mrs. Gordon hugged Suze, then Dewey, then took a long swig from the nearest flask. Someone began to sing, and in the commotion, Dewey slipped away. Ten feet from the celebration she sat down against the rough trunk of a pine tree, hugged her knees to her chest, and began to tremble.

The gadget worked.