Aaron and I are doing reconnaissance, which is a cooler way of saying we’re doing research. That might make my scientist mother and journalist father proud if it were reconnaissance for science or journalism.

But Aaron and I are doing research for my fart machine.

“Okay, walk me through it one more time,” Aaron says.

“It’s an audio-initiated voice manipulator programmed to distort the vocal reception based on tonal input.”

It’s by far my most sophisticated machine to date, something I haven’t had a lot of time to play with ever since Aaron and I started spending every waking minute picking locks at the factory. To be honest, it feels good to be sharing something with Aaron that I know how to do better than him.

Aaron presses the top of his head like it hurts. “So how does it work?”

“I just told you,” I say, trying not to get frustrated.

“No, you just said a bunch of words and strung them together into a sentence. That doesn’t mean you explained anything.”

“How do you know so much about locks and you can’t follow the mechanics of an audio manipulator?”

“How do you keep talking so much without making any sense?”

“Boys, if you don’t mind, I would prefer you maintain a peaceful tone in my store. My patrons have come to expect a heightened state of consciousness when they visit.”

Aaron tries to stuff a laugh, but it escapes in a snort. I elbow his rib and shove him behind a display of healing crystals.

“Sorry, Mrs. Tillman.”

The natural grocer is the first place our reconnaissance has taken us. We’re in need of supplies, and we have reason to believe we’ll find the best ones here.

Mrs. Tillman smiles a tight smile and turns with the stiffness of someone who commands herself to relax.

“Heightened state of consciousness?” Aaron hisses.

“Dude, quiet down.”

“The only heightened anything in here are her wackadoodle prices. She used to buy goat cheese from the llama guy and let Girl Scouts sell cookies under her awning.”

“Goat cheese?” I ask.

“Yeah, I guess he’s got goats, too. Anyway, that’s not the point,” Aaron says. “She used to be nice. Then she goes to this silent retreat, doesn’t talk for two weeks, and when she comes back, she’s selling all these expensive, bogus vitamins and five-dollar ‘candy bars.’”

He puts air quotes around “candy bars,” and I have to laugh because this is the first time I’ve ever seen Aaron get vocally worked up about anything, and apparently he’s got it out for phony, New Age capitalism.

I pick up a bar from a large endcap display. The bar is way heavier than it should be, and indeed it’s marked $4.95, the word SURVIVA emblazoned across the packaging.

“Are these the fart bars?”

Aaron snorts again. “Yeah. Seriously, you’ve never smelled anything like it. Picture a toxic waste dump filled with dirty diapers in a sulfur pit.”

We each grab three bars before making our way to the counter. It’s six weeks’ worth of allowance, but it’s money well spent. All in the name of research.

“Thirty-two ninety-five,” Mrs. Tillman says, this time not even bothering with her tight smile.

“Thanks, Mrs. Tillman,” Aaron says, matching her frown with an extra-wide smile.

“The drugstore by the Square sells candy bars that might be more within your … budget,” she says before handing us a paper bag, and this time she does smile.

On the way back to Aaron’s house, I turn to him.

“So we’ll be testing out the audio synthesizer—”

“At the natural grocer. Absolutely,” Aaron says.

“Good,” I say.

“Good,” he says.

*  *  *

That night, after two Surviva bars and Mom’s famous cabbage rolls, I’m passing enough gas to rocket me to Mars. If only my audio synthesizer were complete, I’d be able to test it. But like a dummy, I left my power drill at Aaron’s house, and besides, he’s the only one with a recorder.

Just then, like it can hear my thoughts, the high whir of a drill floats across the street from the direction of Aaron’s house.

“Oh man,” I grumble, stumbling toward the window. “You’re gonna burn out the battery.”

I haven’t unpacked my charger yet, and because I sort of ignored Mom’s warning to label all my boxes, it’s anybody’s guess where or when it’ll turn up.

I cup my hands against the window and peer across the street to Aaron’s room, but his bedroom light is off. If he’s messing with my drill, he’s doing it somewhere else in the house.

Since I’m way too bloated to go to sleep anytime soon, I slide my window open and pop the screen from its frame. The turquoise house came equipped with an unexpected bonus right outside my room—a trellis sturdy enough to act as a ladder. I’m not exactly the kind of kid who sneaks out of the house when his parents are sleeping, but it’s just across the street, just to retrieve my drill. Besides, it’s easier than waking my parents up and explaining why I need the drill anyway.

I hear the whir of the drill again, but it stops by the time I’m across the street. The streetlight in front of my house flickers, and for a second, I’m standing on Aaron’s lawn in the dark. It’s the first time I’ve been here this late at night, and it occurs to me that I haven’t been invited. The light in Aaron’s room is still off, and suddenly, it feels like I’ve gone from hanging out to trespassing.

The drill revs up again, and I see the faintest light seeping out from the crack of the basement door. The streetlight flickers back on, and I find myself standing closer to the boarded-up basement door than I realized I was. I peer closer at the myriad of locks, only what I see now that I’m closer is more unsettling than any lock.

There are handprints all over the door, smears of black grease that creep around the edge of the door, half covered by the boards and bolts, some with tiny scratches at the tips of the fingerprints, like claw marks made by dragging fingernails.

Suddenly, the drill’s motor cuts out, and the whir sputters, the telltale sign of a dying battery. Then a heavy footfall lands on the steps leading up from the basement, methodically making their way up the stairs.

Straight for the door.

I bolt as fast as I can across the street, the streetlight clicking off just as I reach my house, and all at once, I can’t see the trellis against the wall. I hear the rattle of locks behind me, thumping against the heavy basement door as they’re slowly unlocked.

Groping through the vines in my front yard, I finally find a wooden slat and grab hold of it, wedging my foot in the one beside it before pulling myself up into the window. I reach the ledge of my windowsill just as the streetlight clicks on again.

Just as I hear the basement door swing open behind me.

I don’t turn around. I fall through the open window and take cover on the floor, my heart pounding against the floorboards as I listen for movement across the street.

Heavy footfalls thud against the grass, muffled in the humid, still night. The air is so dense, it feels like whoever is across the street is stealing my breath.

The footsteps leave the grass and move to the sidewalk, closer, their soles cracking over the tiny pebbles on the asphalt. I squeeze my eyes shut and wait for whoever is outside my window to say something, to clamp on to the trellis and climb into my room, to laugh. To do anything at all.

Instead, the person with the heavy step stands perfectly still in the middle of the road, waiting.

I don’t know how much time passes. Maybe a minute, maybe an hour. All I know is that just when I think I’m going to die of suffocation from all that thick air, the steps recede to the sidewalk, then to the lawn, then to the basement door, where the hinges creak to a close and the locks secure whatever secret is worth locking up in Aaron’s basement.

I peer over the windowsill, and when I’m sure no one is still lying in wait in the middle of the street, I resecure my screen and close my window. I lock the latch, but I wish I had a few more locks than that.

It wasn’t Aaron, I’m positive of that. Whoever wanted me to know they knew I was there, they had a much heavier step, a heavier frame.

“Bigger bones,” I whisper, and a chill rattles my whole body.

Because whatever Mr. Peterson is doing in his basement, he wants to be sure I know it’s none of my business. There’s no doubt in my mind—tonight was a warning from my new friend’s dad.

And Mr. Peterson doesn’t strike me as the type to warn someone twice.