His skin was on fire. His lips grazed my neck, and my larynx tensed, ready to scream. My eyelids shot open, my vision glassy and unfocused.

“We belong together. Not to serve your father’s mad experiment. But because we’re the same.” His open palm covered my heart, just grazing the exposed skin above my collar. I gasped at his touch. Fear and thrill were divided by such a fine line that I couldn’t tell which plucked at the tight strings in my chest. And was he really so wrong? I did know about the darkness he spoke of. As much as I loved Montgomery, he couldn’t understand it like Edward.

Something thudded at the door, and the wooden latch splintered. The door burst open. Edward spun around, nearly knocking over the lantern. Montgomery stood three paces away, a gash running down his face, with the rifle aimed at Edward.

“Get away from her,” Montgomery said. Mud streaked his clothes. “I’ll blast a hole in your goddamned chest.”

“Montgomery, don’t!” I yelled. I shouldn’t have cared about Edward’s safety. He was a monster and a murderer and the last person I should defend. But it was too late.

Montgomery paused just long enough for Edward to attack. A low growl rumbled in Edward’s chest before he leapt across the room, knocking Montgomery’s gun to the floor.

I screamed—it was like Edward was suddenly a different creature, wild and violent. Gone were the gold-flecked eyes, now black as night except for an electric ring of yellow iris around slitted pupils. His clothes strained over muscles that seemed to grow larger by the second. The way he moved was calculated, threatening, like he was stalking prey.

He knocked Montgomery down with the force of three men.

I wanted to scream for him to stop, but my voice was gone. Edward was changing. Its bones along my bones, he had said. Its blood in my veins. The animal part of him—the jackal, the fox, along with whatever other bits and pieces of other species Father had added—really did live inside him, lurking, waiting for its chance to transform Edward into the monster Father had made him.

His knuckles were red and knobby, so swollen I thought they might split and seep blood. As I watched, his fingers seemed to grow. Tendons snapped. The metacarpal bones grated against each other. The hair on his arms darkened, until he looked nearly as beastly as the wild dogs that haunted the outskirts of farms.

I dug the heels of my palms into my eye sockets, convinced his transformation must be a trick of my eyes. But when I looked again, it was the same. The palmar ligaments in his hand twisted and popped, bending the fingers. He grabbed the door to slam it shut. The way his gnarled fingers knotted, the sweaty handprint on the door looked as though he had only three fingers. Just like the three-toed prints on the cabin porch. But what animal could he have been made from that only had three toes?

A heron. One of the animals Edward had listed. The realization nearly knocked me flat.

Montgomery struggled to his feet. Blood dripped from Edward’s knuckles, though he hadn’t cut them. He balled his hands in pain and growled deep in his throat. Three black claws slid out between the knuckles of each hand. They were retractable, so that in his human form there had been no sign of them lingering beneath the surface. One claw was missing on his right hand, I realized—cut off by my own shears.

I stumbled and my hip connected hard with the corner of the saddle stand, but I felt nothing. Shock had rendered me blank inside. I’d wanted not to believe it. The change in Edward was hard to define. He was larger. Darker. And yet as my eyes slid over his face and body, I couldn’t name one clear thing that was different. I’d have said his fingernails were black, and yet when I really looked, they were unchanged. It was like looking at stars—one could only see them clearly from the corner of one’s eye.

But the claws, at least, were no trick of my eye. He raised them like deadly knives in Montgomery’s direction. “Edward, stop!” I screamed. But he didn’t seem to hear me.

Edward slammed Montgomery against the wall of bridles with enough force to crack the boards. The seam of his shirt split around his shoulders. He had gotten larger. I rubbed my eyes, trying to see clearly.

Montgomery managed to twist out of his grasp. Leather straps fell, tangling around them. If I could get closer, I could pull one down and try to get it around Edward’s neck like a noose.

Edward curled his gnarled fist. The black claws dripped with blood. Suddenly they retracted, and he punched Montgomery so hard that the wall cracked under his weight.

“Stop!” I said.

But Montgomery got back up. Blood trickled from his mouth. Edward threw another punch that Montgomery evaded. Something silver gleamed in his hand—a snaffle bit from one of the bridles with full-cheek points that protruded from either side of the rings, dangerous as a dagger. Or claws. He slammed it into the side of Edward’s neck.

Edward howled. He wrenched the bloody bit out of his flesh. For an instant he looked like himself again, and my heart twisted. I almost ran to help him.

Montgomery grabbed my arm. “Run,” he said.

But running was useless. Edward was already blocking the door. His claws were out. His face was the dark before a storm. He lunged for Montgomery, ducking just as Montgomery brought down the daggerlike edge of the bit. They fell to the ground, wrestling in the straw. Dirt choked my throat, blinded my eyes. Edward’s claws were like daggers. He swiped at Montgomery, grazing his arm. I pressed my back into the wall, the hanging bridles dangling over me like a curtain. I ripped one down and wrapped the leather strap around my hand, waiting for a clear shot at Edward’s throat.

Just as I was ready to lunge, they rolled, bumping into the table that held the lantern. It fell to the ground. Flames leapt to life in the straw.

“The straw’s on fire!” I yelled.

Montgomery thrust his fist at Edward’s jaw, causing him to fall back long enough for Montgomery to stand. Edward scrambled to his feet, ducking away from Montgomery’s fist. Montgomery swept out his leg, hooking it around Edward’s ankle. Edward slammed to the ground, his head smacking against the corner of the table with a sickening crack.

Montgomery held his fists up, ready to strike, but Edward didn’t get up. His eyes were closed. Blood pooled beneath his head. Suddenly he looked like an innocent young man again, and my heart cried out that we were making a terrible mistake. Had it all been a trick of my eyes? Or my mind? Montgomery felt for his pulse, but I grabbed his arm.

“Leave him,” I said.

“I have to finish it.” He reached for the old iron spade in the corner. An image flashed in my head of the sharp edge coming down across Edward’s neck. My stomach clenched. I stared at the blood trickling through Edward’s black hair, blood that was warm and flowing. A groan so low I could barely hear it slipped out of Edward’s mouth.

Still alive.

I glanced at Montgomery. The spade’s rusted blade was caught on a tangle of leather straps that he tugged on angrily.

A snarl sounded outside. Heat from the fire bathed me in an uncomfortable warmth and then, with a spray of sparks, a roof beam split and fell. I shrieked and covered my head. Montgomery rushed toward me, still holding the spade’s handle. I pulled it out of his grasp and threw it on the floor. “He’s no threat to us now,” I said. “Come on, before we burn with him.”

WE STUMBLED OUT OF the barn into the moonlight.

“Balthasar’s loading the wagon outside,” Montgomery said, in a rush. “I just need to hitch Duke.” He started for the wooden gate, but I grabbed his arm. Duchess, the little mare Father had taken to find Montgomery, stood in the courtyard. She was loosely tied to the veranda rail, her eyes white and wild in the chaos.

I froze. “Father’s back,” I said.

Montgomery paused. Shadows darted in the edges of the courtyard, stealing my attention. “I know. He came back half an hour ago,” he said slowly. “The beasts were after him. He closed himself in his laboratory in a panic.” He ran a hand over the back of his hair, reluctantly. “He expects us to join him there. He said it’s the only place that’s safe.”

“No place is safe.”

He swallowed. “I told him we would gather some supplies and come join him. I didn’t know what else to say. I couldn’t tell him. . . .”

I took a deep breath, feeling the weight of the blood-red building beside us. I pictured my father on the other side of that metal door, listening to the snarls outside as his precious creations tried to find a way to kill him. Waiting for Montgomery and me, who would never come. We’d never see him again, I realized. The laboratory was a fortress. He could survive in there for days, even weeks maybe—if it weren’t for the fire. Smoke was already pouring out of the barn. The laboratory walls were tin, so they wouldn’t burn quickly. He might escape. And then what? Would he start experimenting again?

Something crashed in the salon, and Montgomery grabbed my hand. “Hurry.” We untied Duchess and rushed out of the main gate to where Balthasar was stacking jars in the back of the wagon. He’d filled the few specimen jars I hadn’t destroyed with water for our voyage. They rattled against each other like the glass vials in my wooden box. The treatment was safely stashed in my old carpetbag, which Montgomery had already loaded in the wagon. I did a quick calculation—it would be enough for several weeks. I had everything I needed.

And yet an invisible hand pulled at me from the direction of the compound. It beckoned me back into the flames, to the tin building with burning red paint that bubbled like blood.

“I forgot my medicine,” I said suddenly. The lie made my mouth dry. “I have to get it.”

Montgomery glanced at the billow of smoke rising to the heavens, then turned his attention back to hitching the last few buckles to Duke. “Hurry,” he said from behind sweat-soaked hair.

I darted back inside the compound. The lie gnawed at my heart, but the invisible hand was too strong. The courtyeard all was quiet save the roar of flames—the fire had scared off the beasts. The raging blaze reflected in the salon’s glass windows. Inside I could see the piano, the dining table, the photograph of Mother. The fire would burn every last scrap of memory. And all evidence of my father’s terrible work.

But it was the only way. Such science wasn’t meant to exist. We weren’t meant to rival God. And yet a small part of me wailed to see it destroyed. That part of me—the darkness—would live in me forever, I realized. As long as Moreau blood flowed in my veins. It had driven Father mad. It wanted to do the same to me—and I didn’t know if I was strong enough to stop it.

I hurried to my room and grabbed a plainwooden box so that Montgomery wouldn’t be suspicious if I came back empty-handed. I didn’t let my thoughts linger on the meager belongings I was leaving behind. By morning all evidence of my existence on the island would be gone, too.

I faced the red walls of the laboratory. The invisible hand tightened. The Blood House. Was father inside right now, holed up with some Elk Hill brandy and a good book? Waiting for the rest of us to join him, never suspecting we’d flee and leave him behind?

This was what the hand had been pulling me to—Father. To say good-bye or to claw his face or just to stand outside the door and make my peace while he burned in flames. Some kind of closure.

Beyond the main gate, Montgomery and Balthasar waited for me. I only had to cross the threshold and never look back. Forget peace. Forget closure. We’d sail to London and never spare another thought for the island.

But my feet took me to the laboratory door. The heat from the nearby barn made me sweat. Paint bubbled on the tin, and I let my fingers hover a breath above it. Was he standing just on the other side, waiting for us?

He’d left me behind without a single letter, so why shouldn’t I do the same to him? The newspapers had called him a genius, but they’d never mentioned the little girl he’d abandoned. As far as the world was concerned, Dr. Henri Moreau was a collection of brilliant research papers and a grisly story. Was he more than that to me? Was he a father? He’d thought of me as nothing more than another experiment, a chance to see what happened when humans and creatures bred.