MONSTERS ARE all around us. The thing under the bed that kept you up, spooked and sleepless, in first grade? Totally real. The creature in the lake that your parents called a figment of your imagination? Real, too.

Just because you haven’t seen them—yet—doesn’t mean they’re not there.

Now, I’m the first to admit it: I read lots of books, watch lots of movies, and have an overactive imagination. Yes, I once ran screaming from a museum when I thought I saw a suit of armor twitch. And yes, I had to sleep with all my lights on and a speargun beside me for a week after I saw that shark movie.

But my actual life has officially gotten weirder than my imagination.

And that’s saying something.

The change from normal to loco began on the day my teacher growled. But to really understand it, you have to understand my teacher.

Mr. Chu is the coolest teacher at Monterrosa Elementary—and I’m not just saying that in the usual my-teacher’s-cooler-than-yours way. Everybody thinks so. I mean, sure, he teaches the same subjects as the other fourth-grade teachers, but the way he teaches leaves them all in the dust.

Like how he wore a toga and juggled olives for our unit on ancient Rome. Or how he helped us understand probability by charting how movie sequels nearly always stink like a dead rat in the attic. Or the time he demonstrated gravity by tossing a chair out a second-story window.

After Mr. Chu turned our classroom into a lab and had us figure out how much electricity it would take to bring Dr. Frankenstein’s monster to life, all the kids at school wanted to be in our class.

Mr. Chu was short, stocky, and as bald as an NBA all-star (but without the muscles). He kept order in the classroom with a smile and a calm word, never losing his cool.

Until that dreadful day.

It was oral report time, otherwise known as cruel and unusual punishment. (Even with a great teacher, I’d rather eat live potato bugs than give an oral report. Come to think of it, that would make an awesome report.) Zizi Lee had just finished telling us everything that had gone wrong on her family’s trip to China. She sat down.

Those of us who hadn’t gone yet looked anywhere but at the teacher. I studied the corner of my desktop, where some poor kid long before me had carved BORN TO PUN.

Then I heard it:

“Carlos Rivera,” Mr. Chu boomed in his game-show voice, “come on dowwwn!”

I gulped. Suddenly sweat gushed from my pores like a river and my throat went desert-dry. (Too bad this wasn’t a science report; I had my own microclimate.)

Picking up my shoe box, I shuffled to the front of the room. My buddy Benny Brackman gave me a thumbs-up. His blue eyes sparkled under his mop of curly hair, and he seemed as enthusiastic about my report as he was about anything that caught his fancy. (Or maybe he was just happy he’d already had his turn.)

From two rows over, Tyler Spork made a pfft sound of disgust. His sidekick, Big Pete, snickered.

I tried to ignore Tyler, who was winning the competition for Biggest Jerk in Room Thirteen by a landslide. Setting my box on the edge of Mr. Chu’s desk, I wiped my palms on my jeans and faced the class.

“Um,” I began. Twenty-six faces stared at me. “I, uh…”

Sheer brilliance so far. Obviously, public speaking was a breeze—like tap-dancing on a tiny log as it shot down the rapids.

“Fascinating,” cooed Tyler. “Do go on.”

My face went hot.

Several girls shushed him. I glanced at Mr. Chu, who was frowning into space, head tilted, a million miles away.

I cleared my throat. “My, uh, report is about my dog, Zeppo.”

The teacher made a face as if he smelled something bad. A few kids chuckled.

Reaching into the box, I found a photo and held it up. “Zeppo is a dachshund-Labrador-poodle mix. We call him a doxadoodle.”

Tyler yawned, but some of the girls went awww, like girls do.

I pressed onward. “The, uh, thing that makes me crazy about Zeppo is that he’ll chew anything.” (Our oral report theme was Something That Makes Me Crazy. I told you Mr. Chu was cool.)

Putting away the picture, I lifted something else out of the box. “Exhibit A: my undies.”

This got a huge ewww! from the class. Benny grinned widely. I glanced back at our teacher and noticed him leaning toward the box, sniffing, with this weird look on his face.

“Um, as you can see, Zeppo chewed up almost everything but the waistband. But that’s not all….” I replaced the no-longer-tighty-whities and pulled out a mangled plastic tube. “Exhibit B: our vacuum cleaner. And he didn’t just chomp on this hose—he got the bag and cord, too.”

Tyler leaned across the aisle toward Big Pete and stage-whispered, “What a dweezle. Too bad the dog didn’t chew up his report.”

More chuckles from the class. More blushing from me.

Normally Mr. Chu has a zero-tolerance policy for rudeness. I turned to see why he hadn’t said anything, but he hadn’t even noticed Tyler’s comment. Our teacher was laser-focused, his nose right over my shoe box. In fact, Mr. Chu didn’t even blink when I returned the hose and fished out a second photo.

What was up with him?

“Exhibit, um, C,” I said, showing the picture around. “The wall. Yup, my dog actually chewed on the wall.”

But as I reached for my final item, the mauled tennis shoe, Mr. Chu surprised me. He peeled back his lips and growled—a serious growl, like a Doberman giving one last warning before taking off your arm. His eyes rolled upward, showing only the whites, which totally creeped me out.

All the little hairs on my body stood straight up. It felt like someone had dumped a six-gallon slushie down my back.

Stepping away, I squeezed out a nervous laugh. “Uh, very funny, Mr. Chu. Nice dog impression.”

My teacher kept snarling at the box, like he hadn’t even heard me.

“Mr. Chu?” I said.

Finally, he blinked and shook his head. “Mmm? Oh. Fabulous report, Carlos. Let’s hear it, everyone.”

My classmates clapped, but with some confusion. I hadn’t finished yet. But now, apparently, I had.

Collecting my shoe box, I mumbled a thank-you to Mr. Chu.

He sniffed again, glowered, and muttered, “Dogs,” the way you’d say “cauliflower” if it turned up in your ice cream sundae. Then he scratched at his bandaged hand, which he’d told us came from a “bite from a strange-looking dog” when he was walking past the graveyard last night.

Call it a wild hunch, but something told me our teacher didn’t much care for man’s best friend.

I shuffled back to my desk and stowed my shoe box.

From the next row, Benny caught my eye. Weirdness, he mouthed.

“Weirdness,” I agreed.

But the weirdness was only just beginning.

As we returned from recess, I passed behind Mr. Chu’s desk, where he sat grading homework. What I saw made me stumble over my own feet: on his cueball-smooth head, a tiny forest of short, dark hairs had sprouted.

Since earlier that morning.

And not just behind the ears where he still had a little hair left, but all over.

Benny noticed it, too. “Wow, Mr. C! Your hair’s really coming back.”

Our teacher lifted a hand and ran it over his scalp. “I’ll be darned,” he said. “I guess that emu oil must be doing the trick.”

“Uh, yeah,” I said.

At that, an odd light came into Mr. Chu’s eyes. He gave a high-pitched giggle that lasted an uncomfortably long time—long enough that other kids returning from recess shied away.

I looked over at Benny. “Guess he’s really happy to have hair again,” I said as we returned to our seats.

Our math lesson started out all right—with a scavenger hunt to see how many geometric shapes we could find in the classroom. We all spread out, searching high and low, recording what we spotted.

I’d already found a circle (Mr. Chu’s coffee mug), a triangle (Amrita’s notebook, from above), and a square (Tyler Spork’s head). I was searching for some good parallel lines, when—

“Whoa!”

I turned. Last time I looked, Tina “Karate Girl” Green had been standing on a desk in the far corner, checking the high knickknack shelf. No worries there—Karate Girl was one of the best athletes in class. But now she teetered off-balance.

Tina was going to fall, hard, and no one was near enough to help.

Before I could even open my mouth to shout, a blur whizzed past me, heading for the corner desk. It vaulted a low table as Tina began to topple.

But this was a waste of time. No way could anyone reach her before she cracked her head on the nearest desk. Tina’s eyes went wild and scared as she tumbled.

I winced, waiting for the impact.

And then, just before Tina hit—schoomp!—the strong arms of Mr. Chu scooped her up. Her face was pure amazement.

I gaped. Mr. Chu had raced all the way across the classroom and saved her, in, like, two seconds? Seriously? The same Mr. Chu who claimed that jelly doughnuts were a major food group and that he hid from exercise because he was in the Fitness Protection Program?

What was going on here?

The whole class gathered around, drawn by the excitement.

“Way to go, Mr. Chu!” Big Pete pounded his thick hands together, and everyone joined the applause.

“Wow, you’re so fast!” Amrita gushed.

“Uh, thanks, guys,” said our teacher. He blushed, but under his embarrassment I thought I read confusion, like he wasn’t quite sure how he’d done it.

He wasn’t the only one.

Later, as our class filed out the door to go to lunch, Benny fell in beside me. “What’s the deal with Mr. C?” he muttered, glancing around.

I checked behind us. Our teacher was still at the back of the line, out of earshot. “Beats me,” I said. “All of a sudden he’s Mr. Sniffy.”

“And his hair grows like a time-lapse plant,” said Benny.

“And he’s faster than a speeding bullet. Do you think maybe…?”

Benny nodded. “Of course. It’s obvious.”

“What is?”

“He’s becoming a superhero.”

My face scrunched up. “Seriously? Then what’s with all the hair?”

“Well, maybe he’s becoming a furry superhero, like Wolverine or Black Panther.”

I frowned. “I think Black Panther wears tights. And Wolverine—”

“Doesn’t matter.” Benny waved away my doubts. “We’ve got to research this, pronto, and there’s only one place for that.”

“Yup.”

“The comics store,” we said together.