Ty felt a hand pressing into his ribs, which still ached from the explosion in Geneva and the blast at the DARPA facility. He stirred, but his body was stiff and unresponsive. His brain was foggy, as though molasses were flowing through it.

Another squeeze at his side brought a rush of pain and adrenaline that chased the brain fog away.

His eyes shot open.

It was still dark in the museum.

At his ear, he felt hot breath and heard a soft, sweet voice he knew so well: Nora.

“Ty. Ty, wake up.”

He turned to her, saw the fear in her eyes, and instantly felt himself come fully awake.

Ty sat up and saw what looked like a metal insect crawling toward them on six spindly legs with sharp ends—points that he imagined could drive deep into human flesh.

He rose to his hands and knees, flashlight in one hand, and frantically searched the floor for the handgun he had set down before he slipped off to sleep. He spotted it by the pilot, grabbed it, but when he returned the light’s beam to the spot where he had last seen the robot, it was gone.

Ty swept the flashlight across the deserted museum gift store.

Footsteps pounding in the stairwell drew his attention, and soon the glow of another light raked over him—Kato’s.

He rushed toward them, rifle at the ready.

“What happened?” he whispered, scanning the room.

“A robot,” Ty said. “It was watching us. I think it was going to attack before Nora woke me.”

“I’ll keep the perimeter closer,” Kato said, still searching the room.

“It’s almost my shift anyway,” Ty said. “I’ll watch for it.”

*

In the hours that followed, Ty patrolled the abandoned museum in a state of constant unease.

Every small sound drew his attention. And there were plenty of those small sounds: the creaking of the ruined building, the clattering of falling debris, and the wind through the cracked rotunda.

Every time he heard a noise, he went to investigate. And every time, he found nothing.

Shortly after the first rays of morning light filtered down through the stairwell, it was time for Nora’s shift. But Ty didn’t wake her. He merely watched her sleeping peacefully.

He knew she needed the rest. The physical exertion was one thing, but he knew Nora well enough to know that worry was weighing on her more: worry for the dying pilot and worry for all of them. She felt things deeply.

Lying next to her, Kato slept with his rifle held at his side, the safety on. He had drifted off seconds after lying down. Ty wondered if that was a skill he had acquired as a Navy SEAL—being able to sleep in high-stress environments like active combat.

Other questions dogged him as he marched carefully through the museum. Why were they here? How could they get home? The radio was the obvious answer, but he wanted to be sure about the dial code he used.

As agreed, when the morning sun cleared the Smithsonian Castle, Ty woke Kato, who shrugged off the sleep like a thin blanket and was soon fully awake.

For the next watch, they opted to wake Maria since she had gotten the most sleep that night.

The young woman seemed groggy. Ty wasn’t sure if her sleepiness was from the medication she was taking or from the rough sleep on the pile of clothes on the marble floor.

Maria declined to keep the handgun, insisting that she had never used one and wasn’t confident she would be able to. That admission brought a promise from Kato to train her and a grunt from Maria.

Ty and Kato again exited the Museum of Natural History via the entrance on Constitution Avenue, marching out into the morning light, into the area of the city known as the Federal Triangle, which on Ty’s home world had included the National Archives, the Department of Justice, the Environmental Protection Agency, and the White House Visitor Center. Just outside of the Federal Triangle lay the Ellipse in front of the White House.

As they walked, Ty realized how hungry he was.

“Where to?” he asked Kato, who was turning right on Constitution Avenue.

“I’ve been thinking about that. We need food. And help. But we need one thing more: information.”

“So…”

“We need a vantage point. A place to look out and figure out what happened here. See if we can spot any people or signs of life.”

“That’s going to be tough here in DC. By law, nothing can be taller than the Washington Monument. Or the Capitol. Can’t remember which.”

Kato stopped and stared at Ty. “You can’t be serious.” “What?”

“You grew up in DC, right?” “Yeah.”

“That’s a myth.” “What’s a myth?”

“That buildings can’t be taller than the Washington Monument or the Capitol Building. The height restriction has nothing to do with protecting the views of the Washington Monument or Capitol. It’s just urban planning. The 1910 Height of Buildings Act is what determines how tall a building can be in DC. It’s all based on the width of the street. The idea was that wider streets could have taller buildings—and more narrow ones couldn’t. The cap is one hundred thirty feet—no building can be taller than that, with the exception of a small portion of Pennsylvania Avenue from 1st to 15th Street Northwest, across from the Federal Triangle, where structures can be one hundred sixty feet tall.”

“Interesting.”

“Some buildings were grandfathered in, such as the Old Post Office on the corner of Pennsylvania Avenue and 12th.”

Kato tilted his head toward a sprawling limestone building at the end of the block, which Ty recognized as the Old Post Office. Amazingly, the

structure was still intact. Like many offices and embassies in Washington, DC, the building looked like a skyscraper lying on its side, except the Old Post Office had a prominent square clock tower that rose on the Pennsylvania Avenue side. Ty had been there a few times and had even taken a tour of the observation level, which had an incredible panoramic view of the city.

“The Old Post Office is actually the second tallest habitable building in the city—right behind the Basilica of the National Shrine of the Immaculate Conception, which I believe is only fifteen feet taller.”

“Isn’t the Washington Monument taller than the Post Office?”

“Much,” Kato said as he began to march up 12th Street Northwest. “But it’s not permanently habitable. There are radio towers in the DC area that are taller than the monument, but besides those, it’s the tallest structure in DC.”

Kato glanced backward and to the left. “Well, in our DC. Here, it’s a pile of rubble.”

As they continued up 12th, Ty got a closer look at the building he had always known as the national headquarters of the Environmental Protection Agency. On this world, there was a large sign that read ATF. Growing up in DC, he had been constantly inundated with acronyms, and this was one he recognized, the three-letter name for the Bureau of Alcohol, Tobacco, Firearms, and Explosives.

He tapped Kato on the shoulder and motioned to it. “No EPA.”

“That tells us more about the timeline.” “How so?”

“On our world, the EPA didn’t move in until the early nineties. The ATF was there before. It made sense. For most of its history, ATF was under the Treasury, specifically the IRS. They collected billions in taxes. After 9/11, the Homeland Security Act in 2002 transferred ATF to the Department of Justice and renamed it the Bureau of Alcohol, Tobacco, Firearms, and Explosives. They created a new division for tax collection related to alcohol and tobacco, which is called the Alcohol and Tobacco Tax and Trade Bureau, or TTB.”

Ty stopped walking. “Seriously. How do you remember all this?” “My parents.”

“They were in the ATF?”

Kato smiled. “No. They were strict enforcers of rules, though. And they were passionate about America. They were immigrants. My dad from Japan, my mom from China.”

“So you’re half Japanese, half Chinese?”

“Close. Technically, I’m three-quarters Chinese, one-quarter Japanese. My father’s father was a Japanese soldier who became a textile merchant in the forties after the war. He met my grandmother in Beijing. They had a single son, and he went into the family textile business and, like my grandfather, met a woman in Beijing who he fell in love with. But my parents were obsessed with America. Against their family’s wishes, they emigrated in the seventies. So, I was born here and grew up in North Carolina, but I spent a lot of my summers up here in DC, touring the museums and everywhere else… basically anything that was free or close to it. That was what my parents could afford. To them, this place was like Disneyland. It was to me too. I couldn’t wait to get here every time we came.”

Kato exhaled. “The car rides here were a lot like most evenings at home: my parents quizzing me on American history facts. They were constantly drilling me with all this endless information. I think they thought that if I knew more than anyone about America, I would be unquestionably American.”

“I had a similar upbringing,” Ty said, smiling. “But with science in place of history.”

At that moment, Ty saw a parallel between him and Kato. They’d had similar childhoods, though on different tracks—his of science, Kato’s of history, both rails laid by well-meaning parents who had lost something dear to them. For Ty’s mother, that loss had been Richter, the father figure Ty had longed for but never had. For Kato’s parents, it had been their homeland, which they lost when they came to America.

“When you’re surrounded by something as a kid, it gets down in your blood.”

“Yes, it does.” Kato said. “My parents cared a lot about US history. That’s probably why I started caring about it so much. When your parents reward you for doing something, I think it’s natural to want to become good at that. And I did. I fell in love with this country. I fell in love so hard that when I grew up, I was willing to give my life for it. And sometimes, to neglect my family for it.”

The sun was hot on Ty’s face when they reached the Old Post Office. He walked through the arched entryway, past the foyer, and out into an atrium. There was a glass ceiling above, held in place by a metal skeleton. Stone columns ran from the floor to the ceiling, the railing of balconies running between the pillars. Ty counted ten floors to the top.

“Over here,” Kato said as he shuffled toward a small deli under the overhang. The place was devoid of food or any signs of life. The cash register at the checkout counter was what caught Ty’s eye. It wasn’t a digital register or an iPad with a credit card reader, the kind that was pervasive in the world he had left. These were mechanical devices with a spring-loaded drawer that rang when the merchant made change. It was a device from another time.

Ty searched the abandoned space for a newspaper or any clue about when it had last been inhabited, but he found only shreds that had been ground down nearly to dust by time and pests.

Kato led them out of the café and back to the staircase and up the floors until they reached the highest level of the mezzanine. The skylight over the atrium was cracked in dozens of places, the morning sun poking through. Dirt and grime lay heavy on the glass, a burden left by years of not cleaning it.

Kato strode across the catwalk that looked down on the tables and decaying umbrellas over a hundred feet below. At the elevator, he punched the button, but they both knew what would happen before the panel confirmed it: there was no power here.

At the clock tower staircase, Kato climbed, and Ty followed. His legs were burning by the time he reached the level where he expected to see the Congress Bells. He stopped, his chest heaving, and looked at the empty space.

“The Congress Bells,” he said between breaths. “They’re gone.”

“They were a gift from a British foundation in 1976 at the Bicentennial of America’s independence. They placed them here in April 1983. Obviously, that never happened in this timeline. The British left their homeland in 1940 on this world.”

Kato continued climbing the stairs until they reached the observation deck. There, Ty peered out through the vertical bars at the north side of Washington, DC.

What he saw, in a word, was destruction. The city he had grown up in looked as though a giant rolling pin had run over it, flattening buildings.

In the midst of the carnage, he spotted automobiles sticking out of the debris. They were all American-made, massive, hulking cars with large metal bodies in soft curving forms. To Ty, the cars looked similar to those from his world from the sixties and early seventies. Many had bullet holes in them. They told a story of a city and a time where traveling the streets was dangerous.

Ty panned left. The White House was still standing. So was the Lincoln Memorial to the west. That meant something, he thought—that whoever was at war here, there was some desire to preserve history and the heritage of this place.

To the southwest, Arlington County, Virginia, with its skyscrapers defying DC’s height ordinance, was entirely gone. The ground was dotted by massive charred pits where bombs had fallen. In places, trees had reclaimed the land, a dense forest that grew to the banks of the Potomac.

To the south, the Jefferson Memorial glimmered in the morning light, the George Mason Bridge and Interstate 395 behind it. Both roads over the Potomac River were disintegrating, the concrete crumpling like papier-mâché.

South of the bridges, Ty saw something that surprised him more than the destruction of his hometown: a massive airship floating toward DC. It looked like a Zeppelin from the early 1900s—an elongated, flying football that glided through the air like a massive ship on the sea.

At the bottom, near the front, a crew and passenger compartment hung like a train car affixed there, with windows and large guns mounted at the front and along the sides.

There was no insignia on the ship. “Look,” Kato said, pointing at it.

Ty watched as a massive ramp dropped open at the bottom of the compartment. Figures raced to the end of the ramp and dove, flying face first.

Two dozen people exited the airship before the ramp closed up.

Soon, the divers ripped cords on their chests and parachutes bloomed in the air, slowing their descent. There was no mistaking their destination: they were coming directly for the mall.

To the east, Ty heard a screeching roar. He panned over in time to see three missiles coming in fast.

The airship fired a booming broadside, a dozen shots that intercepted the missiles, exploding them in mid-air over the Atlantic.

Ty didn’t know what the missiles were carrying, but their explosion was like nothing he had ever felt. A buzzing wave rolled across the ruined city. Ty’s legs went weak. His head spun, like a boxer who had just been punched.

He gripped the rail on the observation deck, steadying himself. Another salvo of missiles bore down on the airship, which issued another defensive volley.

Again, the wave from the detonated missiles hit him, a debilitating pulse like an electric shock. To him, it was as though the missiles were carrying ordnance that took a bite out of reality, leaving a hole in its wake.

Ty felt a hand on his shoulder.

“We have to go,” Kato said, dragging him toward the stairwell.

As he turned, Ty spotted the first of the paratroopers touching down on the mall. They were heading directly for the museum—and Nora and Maria.