The next night, I had a frightening dream. I knew I was dreaming, and I struggled to wake up. But I couldn’t escape it.

  A creature chased me across a snow-covered field. Growling, raging at the top of its lungs, it staggered after me on its hind legs.

  Half-wolf, half-man, it raised its hairy snout to the sky and bellowed. Its red eyes glowed like fire, and thick gobs of yellow saliva ran down its furry chin.

  I ran harder, harder. I leaned into a blowing wind and churned my legs, running so hard every muscle ached.

  But my shoes slipped on the snowy surface. It was like running on a treadmill. I ran and ran but didn’t move forward.

  The beast roared closer. I saw it snap its jagged-toothed jaws. I felt its hot, sour breath on my hair and the back of my neck.

  I tried to run harder. Harder. But I wasn’t going anywhere. My shoes slid over the slick snow.

  And then I fell. Facedown.

  The creature leaped on top of me.

  Its red eyes flamed above me. The thick yellow saliva puddled on my face, steaming hot.

  “Nooooooo!” I wailed. I tried frantically to twist away. But it pinned me to the snow. So heavy … so heavy I couldn’t breathe.

  And then the creature opened its jaws. Lowered its head.

  And sank its teeth into my shoulder.

  I woke up with a sharp gasp.

  The beast vanished. The white snow faded to black.

  At first, I didn’t know where I was. It took a few seconds to remember.

  In a strange bed. In a strange room.

  I sat up dizzily and rubbed my shoulder. It ached. It felt so sore.

  From the dream?

  My nightshirt was drenched with sweat. I climbed out of bed and, still shaky, made my way to the dresser. I clicked on the light. Found a clean nightshirt. And changed.

  I glanced at the clock. Nearly four in the morning. Dark outside. And silent.

  Images of the dream floated back to me. The chase. The horrifying roars of the creature. The hot breath on my neck.

  I’ll never get back to sleep, I realized. Maybe if I read for a while, I’ll get sleepy again.

  I took a few deep breaths. “Get over it, Heidi,” I told myself out loud. “It was just a dream.”

  I made my way to the wall of books. Uncle Jekyll’s old books. There must be something here to read, I thought. Maybe I can find something really boring that will put me right to sleep.

  On a high shelf, I thought I spotted a children’s book I’d loved as a kid. I reached for it. But my bare foot snagged on the edge of the carpet.

  I stumbled forward. My shoulder bumped the bookshelf.

  “Huh?” As I caught my balance, a board on the side of the shelf dropped down.

  I moved over to it. A secret compartment.

  I’d bumped open a secret compartment in the bookshelf.

  I brought my face close and peered inside.

  “Wow,” I murmured. “What’s hidden in there?”

  I reached a hand in and pulled out an object. A book.

  It appeared to be very old. It had a brown leather cover. The leather was cracked and crinkly.

  I ran a finger over the faded letters on the front: DIARY.

  An old diary.

  I flipped through the pages. They were yellow and brittle. And covered with words, diary entries written in black ink in a tiny handwriting.

  “Weird,” I murmured. “Who would hide their diary inside a bookshelf?”

  I carried the diary to the chair across from my bed and clicked on the floor lamp. Then, yawning, I settled into the chair and began to examine it.

  I searched for the owner’s name on the inside covers and on the first page. But the covers were blank except for yellow-brown age stains. And the first page began with the diary entry for January 1.

  What year? What year?

  The book didn’t say. No owner. No date.

  I blew dust off the spine. No information there.

  I flipped through the pages again, careful not to tear the brittle paper. Then I opened the book somewhere near the beginning. Squinting at the tiny handwriting, I started to read:

  … So cold today. The snow coming down in sheets, driven by the howling winds. I know I will howl too. I cannot control it. And I will go out in the storm. Because the storm inside me is more powerful than any snowstorm …

  “Huh?” I stared at the yellowed page, gripping the little book tightly in my lap.

  What was this person writing about? A storm inside him?

  Was that some kind of poetry?

  I turned a few more pages and began reading again:

  … I know what I did tonight. I remember every scream, every cry of horror. Those poor people. They don’t deserve it. They don’t deserve me.

  But I am powerless to control it. At night when the urge comes over me, when my body makes its hideous changes … I must go out. What choice do I have?

  I must run and rage and howl. And I must feed.

  I know what I am on those terrifying but exciting nights. I am like a wild beast. And I live for the screams. And for the fear I create

  …

  “Whoa!” I murmured. My heart pounded in my chest.

  Wind rattled the windowpanes. I pulled the quilt from the bed over my chair and snuggled under it.

  I started to read another page:

  … Of course I am a human most of the time. A caring, frightened human. A human prisoner in this old house. And a prisoner in this body that changes at night. A prisoner in this body I cannot control.

  Where does the rage come from? From where does the anger spring—the anger that forces me to kill and destroy? There are two of us trapped here. Two prisoners … the beast and the doctor …

  The doctor?

  I stared at the tiny handwriting, reading those words again and again until they blurred in front of my eyes.

  The beast and the doctor …

  Trapped in one body?

  I shut the diary and studied the worn leather cover. Was I holding the diary of the original Dr. Jekyll?

  Dr. Jekyll, who drank the potion and became the hideous, twisted, dangerous Mr. Hyde?

  But how can that be? I asked myself, gripping the little book tightly.

  Dr. Jekyll wasn’t real—was he?

  And then other questions flooded my mind. …

  Did my uncle find this diary? Did Uncle Jekyll hide the diary in the secret compartment?

  Did Uncle Jekyll study the old diary? Did he learn the original Dr. Jekyll’s horrible secrets?

  Has my uncle turned himself into a monster?

  So many questions!

  I didn’t have time to think about answers.

  I heard footsteps in the hall—and then my bedroom door swung open.

  I tried to shove the diary under the quilt. “Uncle Jekyll?” I gasped.

  No. No one there.

  I realized the breeze from the hallway had swung the door open. I let out a long sigh of relief.

  Shoving the quilt away, I climbed unsteadily to my feet. I flipped quickly through the diary, searching for the secret formula. No. No sign of it.

  I carried the diary to the bookshelf and placed it carefully in its hiding place.

  Then I closed the secret compartment, turned off the lights, and climbed into bed. I shut my eyes, but the tiny handwriting, the frightening words, still danced in front of my eyes.

  The beast and the doctor …

  Did Uncle Jekyll find the formula for the original Dr. Jekyll’s potion? Was it hidden somewhere in the diary? Did he follow the directions and mix it himself?

  And drink it?

  Was my uncle the beast that was terrifying Shepherd Falls?

  I couldn’t stay here if he was.

  I was in terrible danger.

  I had to learn the truth—fast.

  But how?

  Lying in bed, tossing from side to side, wide awake, I thought of a plan.

  I waited until after
dinner the next night. Then I hid in Uncle Jekyll’s lab.

  I found the lab door closed. I turned the knob, pulled the door open, and crept inside.

  The equipment churned and bubbled. On the long lab table, I saw two glass beakers half-filled with a purple liquid. A clear liquid dripped from a glass tube into a gallon-sized bottle.

  Uncle Jekyll and Marianna were still at the dinner table. We’d had a quiet—almost silent —dinner. Marianna kept casting angry glances at her father. Uncle Jekyll pretended to ignore them.

  “Are you going out tonight?” he asked her.

  An odd question. I’d never seen Marianna leave the house.

  “I don’t know what I’m doing,” she mumbled into her tuna casserole.

  I asked to be excused, saying I didn’t want any dessert.

  I knew I had very little time to hide. My uncle always headed straight for his lab after dinner.

  My eyes searched the long, cluttered room. Where could I hide? Where could I hide safely but still be able to spy on Uncle Jekyll?

  A row of dark metal supply closets across from the lab table caught my eye. They looked like the hall lockers at my old school.

  I darted over to them and began pulling open the doors one at a time. The narrow closets were all jammed with equipment. No room for me.

  I heard Uncle Jekyll’s voice out in the hall. He was arguing again with Marianna.

  I searched desperately for a hiding place.

  I’m going to be caught! I realized. He’ll ask me what I’m doing in here. And I won’t have an answer.

  My heart thudding in my chest, I pulled open the last closet door. Yes! Only a few towels on the bottom.

  I took a deep breath and squeezed inside. I pulled the metal door nearly closed—just as Uncle Jekyll stepped into the lab.

  Peering through the narrow opening, I held my breath. Did he see me swing the door shut? Could he hear my heart pounding like a bass drum?

  He moved to the table and inspected the beakers with the purple liquid.

  He didn’t see me, I realized. I slumped against the back of the closet and slowly let my breath out.

  He poured the purple liquid carefully into a rack of slender glass test tubes. Then he adjusted some dials on the electronic equipment at the end of the table.

  What is he working on? I wondered.

  He is working so fast, so urgently. He must be in his lab at least twenty hours a day.

  Why is he working so hard? What is he trying to do?

  I hope it is something good, I prayed. I hope his work has nothing to do with the creature that is wrecking the village.

  Maybe he’s trying to cure a disease, I told myself. Maybe he’s very close. He has almost found the cure. And he is working day and night because he knows he almost has it.

  Or maybe he is in a race with another doctor. Uncle Jekyll wants to cure the disease before the other doctor beats him to it.

  I desperately wanted my uncle to be good. I didn’t want him to be a mad scientist. An evil villain. A … creature.

  Please … I prayed … Please don’t drink your formula and turn into a growling beast. Please … let the people in the town be wrong about you.

  I watched as his hands moved furiously over the table. Pouring clear liquids into purple liquids. Turning knobs and dials. Mixing chemicals from one test tube to another. Holding glass beakers over a flame until the liquid inside bubbled and steamed.

  Electricity sizzled over the table. Uncle Jekyll kept shocking the dark liquid in a beaker with some sort of electric probe.

  His head bent, his shoulders slumped under the white lab coat, he worked feverishly, without ever stopping for a second, without coming up for air.

  I began to feel cramped in the narrow closet. My knees ached. My back ached. Pressed against the metal sides, my arms had fallen asleep.

  This was a big mistake, I decided. I’m not going to see anything interesting at all. I should have trusted Uncle Jekyll. I shouldn’t be hiding in here spying on him.

  I watched him raise a test tube to the fluorescent light over the table. It contained a rust-colored liquid that glowed in the light.

  He studied it for a moment, turning it between his fingers.

  Then he tilted back his head. Lowered the test tube to his mouth.

  And drank the liquid down.

  Oh, no, I thought, feeling heavy dread knot my throat. I pressed a hand over my mouth to keep from crying out.

  Uncle Jekyll licked his lips. Then he raised another test tube with a green liquid inside—and poured that down his throat too.

  He swallowed noisily and licked his lips.

  Then he braced himself. He flattened both hands on the tabletop and leaned forward. As if waiting for the liquids to do something to him.

  I stared through the narrow opening. I couldn’t breathe. I couldn’t move.

  Leaning hard against the tabletop, Uncle Jekyll shut his eyes. His mouth twisted. His knees started to collapse.

  Grabbing the tabletop to keep himself standing, he opened his mouth in a shrill howl of pain.

  His eyes bulged and rolled in his head.

  His face turned bright red.

  Another painful howl escaped his throat. An animal howl. A wolf howl.

  He clamped his eyes shut. He pounded the table with both hands. He tore at his white hair until it stood up in wild tufts.

  His whole face twisted in agony.

  And then, with an ugly groan from deep in his belly, he spun away from the table. And staggered to the door. Staggered like an animal, moaning and growling.

  And vanished from the lab.

  My heart throbbed. My chest ached. I realized I’d been holding my breath the whole time. I let it out in a loud whoosh.

  I pushed open the closet door with my shoulder. And half fell, half leaped out of the narrow closet.

  “I don’t believe it,” I murmured. “He is the beast. Uncle Jekyll is the creature.”

  My head spun. I raised both hands to my cheeks. My skin was burning hot!

  What can I do? I asked myself.

  Who can I tell?

  I’ve got to stop him. I’ve got to get help for him.

  But who can help?

  I couldn’t think clearly. I couldn’t think of anything at all.

  I kept seeing the tortured expression on Uncle Jekyll’s face. And hearing the animal howls that burst from his throat.

  I stared at the empty test tubes lying on their sides on the table. How could he drink that stuff? How?

  I’ve got to get out of here, I decided.

  I turned to the door—and screamed.

  Uncle Jekyll stood inside the doorway.

  He had returned to the lab!

  He was breathing hard, grunting with each breath, staring at me. Staring angrily.

  “Heidi,” he growled. “I’m so sorry you saw.”

  He lumbered toward me, his eyes rolling wildly.

  “Which-what are you going to do?” I stammered. I backed away from him, backed up until I hit the metal closets.

  He grunted in reply. And grabbed my arm with both hands.

  “Uncle Jekyll—stop!” I cried. “What are you doing?”

  “Sorry you saw,” he rasped again. His chest heaved up and down. His breath came in hoarse wheezes.

  “Let go!” I pleaded.

  But his grip tightened, and he pulled me away from the closets. I tried to pull back, but he was too strong.

  He dragged me from the lab. Up the stairs. And pushed me into my room.

  I spun around to face him. “Why are you doing this?” I cried.

  He lurched into the hall and slammed the bedroom door shut. I heard the lock click.

  I dove to the door. “Uncle Jekyll—I can help you! Let me help you! Don’t lock me in here. Why are you doing this?”

  “For your own good,” he replied in a hoarse animal growl.

  I heard his heavy footsteps going down the stairs.

  I tried the do
or. Locked. He locked me in.

  “Uncle Jekyll—” I called.

  I knew he couldn’t hear me. I heard the front door slam.

  I ran to the bedroom window and peered out into the darkness.

  After a few seconds, he staggered into view. I took a deep breath and tried to slow my racing heart as I watched him make his way down the hill toward the village. After a minute or so, he disappeared into the shadows.

  “Why?” I murmured, shaking my head. “Why?”

  Does he plan to keep me locked up in here forever? I asked myself.

  No. He can’t.

  And then I thought of an even more frightening question: What does he plan to do with me when he gets back?

  Through the open window, I heard a shrill scream. And then frightened shouts from down the hill.

  “I have to get out of here,” I told myself.

  I tried tugging the doorknob with all my strength. Then I tried to batter the door open with my shoulder.

  No way. The door was solid oak.

  I dove to the window. I heard more screams from town. Flames shot up. More angry cries. A siren wailed.

  I leaned out the window and looked down. A two-story drop straight to the ground. No tree to climb down. No shrubs below to break my fall.

  “I can’t jump out,” I decided. “I’ll break my neck.”

  Then I spotted the metal rain gutter at the corner of the house. Rusted, its paint peeling, it ran along the roof, then straight down nearly to the ground.

  If I can wrap my hands around it, I can slide down, I decided. But will it hold my weight?

  Only one way to find out.

  I leaned farther out the window and reached for it … reached …

  No. It was inches from my grasp. I couldn’t lean any farther. I couldn’t reach it.

  Wait, I thought. I ducked back into the room and pulled the desk chair to the window. My legs trembling, I climbed onto the desk chair. Then I leaned out the window again.

  Reached … reached for the gutter.

  My fingers brushed the rusted metal—

  —and then I lost my balance.

  I felt my body plunging forward … plunging out the window …

  … and I fell.

  I screamed—and grabbed wildly for the gutter.

  My hands wrapped around it. The rusted metal scraped my skin.