“What the fuck are you doing in here!” a man shouted, and a shadow suddenly filled the doorway behind the woman. Holy shit, he’s seven feet tall! Trix thought, and though perhaps panic made him seem taller than he actually was, he was certainly big enough to do them both a lot of damage.

The dog had not pounced. It was hunkered down, hackles bristling, teeth still bared.

“We’re not here to cause a problem!” Trix said, and behind her Jim opened the door at last.

The man was stepping past the woman, moving her gently to one side with a protective arm pressed across her chest. His other arm hung at his side, hand fisted into something resembling the head of a sledgehammer.

“Trix,” Jim said softly.

“What?” another voice said. The girl stood at the head of the stairs, headphones still on and the music player clasped in her hand. Her mouth hung open in surprise, eyes flickering from Trix and Jim to the dog to her parents, then back again.

“We’re leaving,” Jim said.

“Damn right you are!” the man shouted, and he darted across the hallway. The dog leapt then, tangling in the man’s feet and sending him stumbling toward them, hands outstretched, eyebrows rising in surprise as momentum threw him forward.

Jim tugged Trix through the doorway, and the man’s left hand closed around its edge, clasping tight to prevent himself from falling over. Trix saw the dog cowering back against the lowest stair, ears flat against its head, head lowered, eyes staring up at the big man. Behind and above them, the teenager seemed frozen in place.

“Trix, run!” Jim said, and he pulled her out into the dark. She turned her attention from the shocked and angry family behind them to the ground beneath her feet, startled by the three steps down to the street that had not been there before. Jim’s Mercedes was no longer parked at the curb—of course not—and in its place stood a big station wagon, glittering with droplets of rain.

They hit the sidewalk and turned right, running along the street, listening for sounds of pursuit, and Trix wondered whether Jim was feeling as dislocated as she. There were no obvious differences around them, at least not immediately. But she felt not only that she had not been here before, but never could have been. She glanced back at the home they had just left—Veronica’s house, in another world—and it was nowhere near the same. The front door still stood open but no one looked out, and she wondered at the scene taking place in there right now. The wife calling the police, perhaps, husband bristling, dog slinking back into one of those dark rooms, the teenager watching from above with a kind of detached surprise. At least they weren’t following. At least—

A shadow appeared at the open doorway, big enough to be the man. And he had something in his hand.

“Jim, gun!” Trix said, and they ran faster. Surely he wouldn’t fire at them in the street? Would he really shoot at all, even though they’d actually done nothing? With every step she expected to hear the sharp report of a pistol and feel the bullet’s impact, and by the time they rounded a corner she was panting hard, fear running cold down her back.

“Keep running,” Jim said. “Just in case.”

“In case he’s following?”

“It’s not as if we can explain,” he said, and it was as close to humor as either of them could find right now.

They ran on, side by side now, and Trix realized what an unlikely pair of joggers they would make. Jim was wearing jeans and a dark button-fronted shirt, having left his jacket in Veronica’s living room. And she wore tight black trousers stitched with several zips, a vest top, and a light jacket. Running, they were so obviously fleeing something that they might as well have painted “guilty” on their foreheads.

At the next road junction she grabbed Jim’s hand and pulled him left, then leaned against a high timber fence and tried to catch her breath. “Can’t keep running,” she said, and he nodded his understanding.

“We’d know by now if he was coming after us,” Jim said, glancing nervously back the way they had come. He was panting, as was Trix, but she thought it was more out of surprise and fear than exertion.

“So what now?” she asked, though she had already figured where Jim’s first instincts would take him. He’d promised to deliver those letters, yes, and they’d both sworn not to open them. But Jim had not promised to go directly to this Boston’s Oracle. Veronica must have known that he never would, and had not burdened him with the need to break that promise. In Trix’s eyes, that gave the old woman more of a human aspect than anything else she’d said or done.

“Now we find Jenny and Holly,” Jim said. “My apartment, your place, Jenny’s parents’. The first thing she’d do is go somewhere familiar. If this is even the Boston they slipped into.”

“If anywhere’s familiar,” Trix said. “Don’t you feel …?” She shrugged, because exactly what she felt was difficult to express.

“Yeah,” he said, glancing around at the buildings surrounding them. There was nothing too unusual about them, no unique construction methods or materials. But Trix felt totally out of place here. Perhaps it was a combination of many smaller factors—the air carrying an unusual taint, the sky hazed with a different level of pollution, the echoes of unknown voices singing on the breeze—that made her shiver. It was as if they were being watched, and it was not the last time she would imagine that.

That cityscape, she thought, able to dwell on it for the first time. It’s one of those I’ve had nightmares about—one of those Bostons where I’m now dead—and Jim has painted it, and it’s almost like …

As they turned from Prince Street onto Hanover—the smells of the North End’s restaurants almost inescapably tempting—a car cruised by, three teenagers inside singing along cheerfully to a song pumping out of the radio speakers. One of the girls looked at Trix and smiled. They sang in English. It surprised Trix, though it shouldn’t have. This city might be some kind of parallel world, but it was still Boston.

“We need to get a cab,” Jim said.

“Yeah. Carless now.” She watched the teens’ car drift along the street.

“It’s going to be nearly impossible to get one here. Maybe out on the main road, whatever it is that runs over the Big Dig. Otherwise we can head toward Quincy Market. It’ll be easy enough to find a cab there. That’s probably better, getting some distance, just in case those people called the cops.”

“And if they have?” Trix said. “What would we do? How would we explain who we are?”

“We’d just …,” Jim said, voice disappearing into a shrug.

“In this Boston, we’re both dead,” she said. “Husks in the ground, or dust if our families had us cremated.” She shook her head, trying to absorb the strangeness of that truth. Every breath I take contains molecules I’ve breathed before in another body.

“I don’t care,” he said. His face changed little; there was no dawning realization, only acceptance. “I’m only here for one thing.” As he turned from her, she saw him check that the two folded envelopes were still in his back pocket. Each had been marked with a name and an address, and she was keen to check them out right away. But this was all for Jim. For now, she would follow his lead.

Less than ten minutes later they flagged down a cab on North Street. The driver was a big, cheerful Irishman, and he turned down the Celtic-punk CD just enough to be able to shout over it. Something about this comforted Trix, though at first she couldn’t quite place what it was. Jim shouted his apartment address, the driver waved a hand and pulled out into traffic, and the music provided a drum-and-fiddle theme to their journey. It was as the Irishman started shouting about roadwork and how the city still wasn’t spending enough on road maintenance that she was able to sink back into her seat and relax. He doesn’t see anything different about us, she thought. To him we’re normal. Clasping Jim’s hand, she closed her eyes and rested.

I wonder if Trix is feeling this as well, Jim thought. The sense of being followed was subtle, an itch on the back of his neck and a tightening across his scalp. He did not turn around to look back; all he’d see would be headlights, vague shapes walking along pavements, shadows in this place where he should never be. The feeling was slight. And besides, whoever followed them would be at home in those shadows.

He looked forward past the big driver at the streets unrolling ahead. Trix’s hand felt solid and real in his, and he gave her a slight squeeze, smiling when she squeezed back. The driver was speaking, but his words were all but lost in the rush of music blasting from the speakers. Amid such cacophony, Jim found it ironically easy to rest and gather his thoughts.

From what he’d seen of the skyline from the upstairs window in the house they had just fled, this Boston looked quite different from the city where he had been born. How strange that a few significant changes could affect the view so fundamentally, even though ninety-five percent of the city was probably nearly identical.

Yet already he felt so much closer to Jenny and Holly. He and Trix had come through into this reality from another, stepping across the threshold with little more than watery eyes and a sense of shock at their accomplishment, and maybe somewhere in this Boston, Jenny and Holly were breathing, living, striving to discover what had happened to them and waiting for him to find them again. Though this was a strange city, the sense of being an invader here was rapidly fading away.

He could feel the folded letters in his back pocket. Soon they would go to the first of those addresses and look for the first name, but before that he had to see for himself just how different this place was. As Trix had said, both of them had died in this reality and left their loved ones grieving, so his apartment would belong to someone else. But it was the first place Jenny would have checked, and perhaps …

“Perhaps she’s still there,” he muttered.

“What’s that?” the driver called.

“Nothing,” Jim said, raising a hand. “Turn the music up.”

“That I can do!” The driver flicked a dial on the dashboard, and the music roared louder, filling the car and allowing Jim to clear his head.

“She might be,” Trix said, leaning into him and resting her head against his shoulder. “But if I know Jenny, she’d have moved on.”

“Holly will be her priority. She’ll be trying to figure out what the fuck has happened, but she’ll be steered by Holly. They’ll have to eat, and have somewhere to sleep. And if they can’t find anyone who knows them, it’ll be a hotel.”

“Providing she came through with money.”

“Yeah,” Jim said. “And providing the currency here is still dollars.” He wondered what would happen when it came time to pay the cabdriver. He reckoned he had fifty bucks in his pocket, but would the driver recognize the president on Jim’s currency? And beyond that … would they have to steal? And if they were arrested, what story could they give? Their names here matched those of long-dead children.

As they left the North End, Jim took more notice of their surroundings, leaving the problems of money and identity until later. The overall impression he’d gleaned from that brief look at this new Boston’s skyline was becoming more refined now, and initially he was surprised by how little had really changed. The JFK Federal Building was still there, which told him plenty, and Boston Common was still a welcome oasis of nature within the city. It was across the Common, roughly in the theater district, that the cathedral they’d seen from the house rose toward the night sky. It was well illuminated by display spotlights, proudly flaunting its magnificence over the lower buildings surrounding it.

“That is massive,” Trix said, and Jim realized she was leaning across the backseat with him to get a better view.

“What’s the cathedral’s name?” Jim shouted, taking a risk. The driver glanced curiously at him in the mirror, then grinned again and switched into a new, even more verbose mode. Tourists, he must have thought, and Jim vowed to keep an eye on their route.

“That’s the world-famous Cathedral of Saint Mary in the Park, and that in front of it is Saint Mary’s Park. Green an’ lovely, even at night.” He turned the music down, and Trix glanced at Jim and raised her eyebrows. What have you started? But this was good. They needed information, needed to know what this Boston held for them. And who better to ask than a taxi driver?

“Almost thirty years to build, and fourteen souls taken into the cathedral’s bosom,” the driver said. “If you visit it on your stay, make sure you take a look at the shrine in there, built to those brave souls. Beautiful, it is.” He looked in the mirror again, the smile slipping.

“Where are you from?” Trix asked.

“Well, you’re asking me two different things there, young lady,” the driver said, his good humor restored. “As to where I was born, that was Cork back in the home country. But where I’m from?” He waved both hands around him, holding the wheel with his knees. “Lived here since I was three years old, and never been back. So anyone asks where I’m from, I say Boston. Who wouldn’t, eh?”

“Who indeed,” Jim said. A few raindrops speckled the cab’s windows, smearing his image of the cathedral, and he wondered whether Jenny and Holly were getting wet in the same shower.

“You’re here visiting?” the driver asked.

“Looking for someone,” Jim said. Trix tapped his leg, but he moved her hand aside. Why shouldn’t he tell the truth?

“Who’s that, then? Maybe I can help.”

“I doubt it. So … I haven’t been to Boston before, would you believe? The Irish influence is big?”