“Don’t. Or won’t?”

“Can’t,” he answers. He’s never set foot in a confessional, but he speaks with the urgency of the penitent and the resolve of the faithful. “I can’t let her go. I can’t . . . accept that in an infinite number of worlds, there’s not even one where Amanda and I can be together.”

Not for the first time, Jonas watches pity pass across Eva’s face. “But you have to accept it.”

“Why?” He honestly doesn’t know.

“Because you’re fighting the universe.”

“I know,” he admits. “But so what?”

“So the universe is going to fight back.”

The words prove prescient as the driver’s side of the car suddenly caves in, crunching glass and rending steel. The impact sends Jonas flashing back to another road in Switzerland not all that different from the one he’s on right now. History has a way of repeating itself, so the saying goes, and there must be a reason for the axiom. What if there is an infinite dance of events, fated to unfold in the same movements, over and over and over into infinity?

He sees Eva clutching the wheel, wrestling it for control of the car. Wind shoots in from what had been the driver’s side window. Jonas peers through the jagged aperture and sees the cause of the collision—an eighteen-wheeler as big as a small house running alongside them.

His mind races, grasping for an explanation. The driver is drunk. Or fell asleep at the wheel. Or is simply negligent. But all these possibilities are dashed when the truck escapes from its lane again, missiling back toward the FIAT, once more digging its mass into the car’s crumpled side.

Jonas hears Eva scream, her wail carrying both terror and confusion. On some level, they both know the truism that one time is an accident, twice is deliberate.

This is an attack.

Eva deftly tries to keep the car on the road. She floors the accelerator, coaxing as much speed as she can from the FIAT’s modest engine, and Jonas suspects that they both have the same instinct: they won’t survive another collision. Their only chance is to race off the elevated highway to more level ground with enough space to get away.

The truck is drifting back—positioning itself for another assault—when Jonas sees the driver. Amazingly, impossibly, Jonas knows him. The driver’s face is unmistakable. It belongs to a dead man.

The driver is Macon.

Jonas’s first thought is that he’s hallucinating. Macon here—in this specific time and place, acting with malicious intent—has to be a mirage conjured by adrenaline. But while Jonas might deny his lying eyes, there’s no mistaking the reptilian coldness in the driver’s. Whoever this universe’s Macon is, and for whatever reason, the man clearly intends to kill him.

Jonas watches Macon’s face contort with malice as he aims the truck at the FIAT. He barely notices the gunmetal-gray bracelet on Macon’s wrist before the truck hurls into Eva’s car again, a battle at sixty miles per hour between a David and a Goliath. But this time, David has no slingshot.

Eva is screaming. Or maybe that’s just the sound of tortured metal as the truck sandwiches the FIAT against the guardrail. Steel wails as the Seidenstrasse begins to stretch over Lac Léman. The truck recedes once more, and then slams into them again. The guardrail crumples, and the FIAT is airborne.

Instinct and sad experience impel Jonas into action. Snapping off his seat belt, he envelops Eva. A million times, he has relived the accident with Amanda, and a million times he has embraced her as he wishes he had on that fateful night. Tonight, he swallows Eva in his arms the way he wishes he’d done his wife, hoping it will mean the difference between life and death.

Closing his eyes, he tenses, knowing from experience what happens next. Impact. Violent and abrupt. The sound of the world ending. Old Testament brutality and tumult.

The FIAT slams into concrete. No, not concrete. The waters of Lac Léman. The car begins sinking instantly, plunging into the inky darkness. Water gallops in through the mangled driver’s side. It smashes against Eva like a fist. And with each ounce that cascades in, the car’s descent quickens.

It’s the smallest of miracles that Jonas had the instinct to unbuckle himself. If they survive this, that will be the reason. Holding his breath, his fingers fumble with Eva’s seat belt, but the water makes both skin and metal as slick as ice, and his hands struggle to find purchase. Eva’s eyes go wide with shock and fear as she discovers she’s unable to keep her mouth closed, to resist the primal urge to breathe. Her mouth births tiny bubbles of carbon dioxide. They float gracefully from her lips. The last thing she’ll ever see . . .

Jonas feels his fingers give way beneath his efforts. His heart leaps at the realization that it’s the seat belt surrendering. Eva is free. Jonas allows himself to feel relieved until he sees the cloud of crimson rising from Eva’s midsection. Panicked, his lungs burning, he looks down and sees an angry metal shard protruding from the driver’s side door, impaling Eva’s abdomen.

His body goes cold. This isn’t how Amanda died, but it’s close enough to torture his soul. Maybe it’s the urgency of Eva’s predicament, or just oxygen deprivation, but conscious thought leaves him. All he knows, all he cares about, is extricating her, and he feels this with terrible urgency.

The next few seconds blur. Untangling Eva from the seat belt, wrestling her from its nylon grasp. Pulling her from the metal’s jagged grip. The horror as the murky water turns red. The impotent attempts at opening the door, and the realization that the weight of Lac Léman won’t yield to it. Jonas pulls himself, and then Eva, through the broken window, glassy shards scraping at them like rows of gnashing teeth.

Seconds later, Jonas is exploding out of the water—miraculously—with Eva in his arms. He manages to beach them on the shore. The ground is hard, unyielding, and terribly cold, but Jonas greets it as a gift. He pushes Eva onto her back and readies himself to perform CPR, though he knows only what he learned from a junior high class and God knows how many movies.

He alternates between chest compressions and blowing life into her lungs. As he retracts his lips from hers, he tastes copper. Which means internal bleeding. He’s losing her. He redoubles his efforts, leaning down, the butt of his hand pressed to her sternum. “C’mon,” he whispers. “C’mon . . .”

He moves back to her head, pinching her nose with one hand and keeping her mouth open with the other, ready to deliver another series of breaths, when she coughs violently. Fresh water flecked with blood geysers up unexpectedly as her eyes fly open, disoriented and scared and confused.

Jonas’s mind flashes to the image of Macon behind the wheel of the truck. What was he doing? And why? It couldn’t possibly be a coincidence, could it? “Just—try not to talk, Eva. Just breathe. Just breathe.”

As Eva does her best to comply, Jonas considers her abdomen. The wound beneath her rib cage glistens, spurting blood with each beat of her panicked heart. His hands work to stanch the bleeding, but he feels Eva’s warmth flowing between his fingers.

“Jonas,” she says, each syllable a labor. “I feel cold.”

He starts ripping away at his shirt, tearing strips for a makeshift bandage, when he hears the sirens. They’re growing louder. Closer. He packs Eva’s wound with the remains of his shirt, but the fabric quickly goes damp with her blood.

“You have to go,” Eva says.

“I’m not leaving you.” If Jonas knows anything, he knows this.

“I’m leaving,” she whispers.

“We’ll get you to a doctor.”

“Too late, I think.” She shudders. An involuntary spasm, as if she’s about to fall asleep. Sirens echo in the distance. “You can’t let them arrest you,” she says.

“They won’t.”

“They might.” She draws a jagged breath. “You’re at the scene of an accident. And if they take you into custody . . . they’ll take your tether.” She clenches her teeth, willing herself to get out the undeniable conclusion. “You have to go.”

She’s barely uttered the words before everything is bathed in red light.

“Geh runter!” Jonas hears. “Geh weg von ihr!”

Next, footfalls. The sound of men vaulting a guardrail. The jangle of equipment and the clatter of guns.

“Don’t be sad,” Eva says. Contentment on her face. “It’s okay. There are other realities where I’m alive.”

Emotion overwhelms him. Sadness. But also guilt. The knowledge that Macon must have been after him. That she’s dying only because he came into her life. “Thank you,” he says, fighting back tears. “For everything.”

But she’s gone. He fears she never heard a word. A tide of grief washes over him. Not as visceral as when Amanda died, but no less profound.

“Geh runter! Geh runter!”

Swiss police surround him. Guns aimed. Voices raised. Eva was right: this is now a crime scene, and everyone present is a suspect. Jonas allows for the possibility that the police in this reality are particularly prone to outsize reactions.

“Beweg dich nicht!”

He doesn’t react to them. He doesn’t turn away from Eva. He’s thinking. Presented with an impossible choice. Eva was right: if he’s taken into custody, they might confiscate his tether. He calculates his likelihood of getting lucky—either by persuading them to let him keep the tether or reclaiming it before he reality-slips without his ring—as extraordinarily low. But to leave this universe would mean leaving its Thibault and the man’s promise of identifying the reality where Amanda is still alive.

“Beweg dich nicht!” They’re addressing him like a suspect. Jonas ratchets down his odds of retaining the tether in police custody, comparing them with the odds of divining Amanda’s location without Thibault’s help.