I should have been able to stop it!

I summoned everything I had left in my body. I threw myself across the last few steps and launched into the air, colliding hard with his back and knocking him to the ground. Pain exploded in my gut, tearing open my wound, unleashing a sea of blood. I took Dylan’s head into both of my hands and slammed his skull against the concrete. Then I did it again, and again, hearing the bone crack. When his eyes finally closed, I wrapped my hands tightly around his throat and pushed my thumbs into his windpipe. I cut off every atom of air that would keep him alive.

Above me, Karly screamed.

Of course she did. She couldn’t see my face. I was a stranger attacking her husband. She grabbed my shoulders to pull me off, and when I hung on, she kicked and scratched and got on the ground and clamped her teeth around my forearm. I couldn’t take it. Finally, I let go, and she dragged me backward into the grass.

We were still in the dark. She couldn’t see my face.

“Karly, stop!” I screamed.

But all her primal instincts had taken over. She hammered my body with her fists. Her knee sank into the bloody mess of my abdomen, causing waves of agony that left me struggling to breathe. I put up my arms to fend her off and shouted again.

“Karly, it’s me!”

My familiar voice, my words, slowly seeped into her mind. She began to perceive that something impossible was happening here, but it was already too late.

Rising above her like a ghost under the park light, I saw my doppelg?nger. He was on his feet again, the knife in his hand. Blood from his fractured skull ran in ribbons down his face. He jumped toward my wife. With a surge of adrenaline, I shoved Karly away, but Dylan kept coming. He landed on top of me, and we rolled together, battling for control of the knife. My strength was waning, but so was his. Both of us were dizzy, drained, desperate. The park became a whirling gyroscope inside our heads, and I could feel our minds coming together. I saw his face and my face through my own eyes. As we rolled, as our bodies intertwined, we were becoming one person. We’d always been one person, trapped inside endless worlds.

There was only one way to stop him. I had to sacrifice myself. I let go of the knife and took hold of his throat again, choking him. With his hands free, he thrust the knife into my back, and pulled it out, and thrust it in again. I held on through every lightning bolt of agony. I ignored the pain and weakness and blood and kept my fingers wrapped around his windpipe. Below me, his face turned purple. His eyes bulged. His tongue swelled from his mouth. He stabbed me over and over, but the shock waves rippling through my back belonged to someone else, not me. My mind shunted them aside. I had no wounds, no feeling, no body at all. I was nothing but two hands locked around a killer’s neck.

He reared back to stab me one more time.

This time, the blow never came. His arm stiffened in midair. The knife slid away from his fingers and dropped to the grass. His stare grew fixed, the whites of his eyes ruby red with exploded blood vessels. His body went limp.

It was done.

Dylan Moran was dead.

It took time for me to unclench my knuckles and peel my fingers away from his neck. When I was finally able to let go, I rolled off him. We lay in the park next to each other, two twins. One dead, one dying. I turned my head, watching him, still not able to believe I’d killed him. Exhausted, I let my eyes blink shut—not for long, only for a few seconds. When I opened them again, he was gone. The ground was empty, as if his body had never been there at all. He was an intruder who didn’t belong in this world.

Neither did I.

I had to go, too.

Every breath had become torture. I dragged in air and tasted blood as I exhaled. It wouldn’t be long. And yet I felt free.

Karly knelt by my side. Her blue eyes were full of confusion and fear. “Dylan. Oh, my God, Dylan, what’s going on? That other man, he was you. He had your face. Where is he? Where did he go?”

I whispered to her as my brain floated. “Go home, Karly.”

“No, you need help. An ambulance.”

She took her phone in her hand, but I found enough strength to hold her wrist down. “Don’t.”

She put her hand softly on my cheek. “I can’t lose you. Ellie can’t lose you.”

“You won’t lose me. Go home. I’m there.”

“What are you talking about?”

“I’m not your Dylan. I’m not him. Your Dylan is safe. I promise you.”

“I don’t understand!”

I felt black clouds encroaching. I didn’t want her to see the end. “Please, Karly. Go.”

“How can I leave? How can you say that?”

She bent down, and her hair swished across my face. Her lips found mine. I could barely feel them, but the barest sensation of softness was enough to take away some of the pain. She held on to me, our faces pressed together. I smelled her perfume, but my five senses had begun to shut down, and only the sixth was left.

“Do you love me?” I asked her.

“You know I do.”

“Then trust me. Go home.”

She pushed herself up on her hands, her face over mine, only inches away. “Are you really there?”

“Yes.”

“How can I possibly believe that?”

“Because I would never let you go.”

She stared down at me, trying to find answers in my face. I felt her kiss me again, slow and soft, like a fairy touch. She got to her feet and stood over me, memorizing the look of me, the way I’d memorized her.

“Come find me, Dylan,” she murmured.

I tried to speak, but I couldn’t.

“Come find me,” she said again. “I’m still here.”

Then she walked away, not looking back. I followed her with my eyes until the darkness of the park enveloped her. She was in her world; she had her husband and her child. I was alone again.

I lay on my back, staring at the sky. Stars ran across the heavens in limitless numbers. There was no more pain at all. My blood was on the ground, but I doubted it would be here for long.

My chest swelled with one last breath.

It gave me the strength for one last word.

“Infinite.”

CHAPTER 33

“Welcome back,” Eve Brier told me.

I still lay on my back, but instead of a field of stars above me when I opened my eyes, I saw the white foam tiles of an office ceiling. Beneath me, the damp grass of River Park had been replaced by a leather sofa. Instinctively, my hands went to my abdomen, where I expected to feel blood gushing from an open wound. Not anymore. I was completely uninjured.

With a jerk, I sat up, trying to orient myself. A little bit of nausea lingered, as well as a splitting headache. “Where am I?”

“Hancock Center,” Eve replied. “My office.”

She sat across the room from me in a cushioned roller chair near a row of floor-to-ceiling windows. Behind her, I could see the expanse of Lake Michigan, a view that was interrupted by one of the building’s huge diagonal crossbeams. On the horizon, the blue of the water met the blue of the sky.

Eve cocked her head over her bony shoulders. She had an enigmatic smile on her face. Her almond-shaped eyes still looked alien. She had a pen in her hands that she stroked in an oddly suggestive manner. Her lush blond-and-brown hair swept messily across her shoulders. She pulled her chair close to the sofa and leaned forward, looking at me with an intense, curious expression.

“Did you go there?”

I knew what she meant. “The Many Worlds? Yes, I did.”

“Was it what you imagined?”

I didn’t know how to answer her. I got off the sofa and had to brace myself, because my legs were unsteady. I crossed to the windows and stared at the vista. Chicago looked the same. “Why are we not at Navy Pier? How did we get here?”

“Navy Pier? I don’t understand.”

I turned away from the windows. “That’s where you gave me the injection.”

Eve shook her head. “No, we’ve been in my office the whole time.”

“I’ve never been to your office before.”

“Actually, you’ve been here half a dozen times. We’ve been working through your grief over Karly. But today was the first time we tried my new therapy.”

I sat down again and tried to puzzle out what was happening to me. By saying the escape word, I should have gone back to my world. The real world. And yet my surroundings all felt brand new.

“How long?” I asked.

“What do you mean?”

“How long have I been here?”

“Today? About five hours. That’s quite a bit longer than most of my patients experience in their sessions. I was starting to get concerned. If it went on much longer, I was debating how to bring you back. But I assume you finally said the escape word.”

“I did,” I said, after a moment of silence.

She sensed my hesitation. “Dylan, it may feel strange, but you really are back where you belong.”

Was I?

Then why did everything feel different?

“I don’t remember any of this,” I told her. “Your office. The sessions we’ve had. I don’t remember the past few weeks at all, other than being in the Many Worlds.”