When Milo got to the river’s edge, where the log fern gave way to a rough bank, Buck was already there. Shirt tied around his waist, his lean thirteen-year-old’s torso glossed with sweat, bent over with his hands on his knees. There was something in his face Milo didn’t like.

“Drop something?”

Buck startled and turned. “Nothing important. What took you so long?”

Milo swatted away flies that had found a perch on his glasses. “Had to get Ma’s laundry list of ‘don’ts’ before she’d let me go.” His grin took up little of his mouth, which was always trying to suck it back into his teeth. “‘Don’t swim in the water. Don’t eat anything you catch. Don’t touch any poison ivy.’”

Buck turned away to pick up his rod, shaking his head. “‘Don’t wipe your own butt. Don’t have too much fun.’”

“‘Don’t let Buck pressure you into drinking beer.’”

His back still turned, shoulders gleaming in the afternoon sun, Buck worked a worm onto the hook. A humid silence, thick and sticky, fell between them. Milo sucked his grin all the way back into his mouth and toed the dirt, looking for his own worm. He unearthed an old soda bottle, a piece of rubber that he hoped wasn’t a condom, a rock with what looked like blood on it, and a can of beer crushed in on itself like an imploding star.

After he found a worm and pushed the hook through it, he turned to the greenish water and cast off. Buck did the same; his cast plunked down too close to the bank.

“Weak!” Milo laughed.

“Shut up. There’s good fish over here.”

“Like what?”

“Like your mom.”

Dark shapes drifted under the surface of the murky water.

“Let’s make a bet, then,” said Milo, feeling bold. “Yours is bigger, I’ll write your history paper for you. Mine’s bigger, you have to sneak into Old Man Ronnie’s coop and steal a carton of eggs.”

“You’re nuts. The guy’s a loon. He’s got it surrounded by barbed wire ever since last Halloween when Simon and his crew egged half of Porter Street.”

“There’s an opening at the bottom of the fence. And he’s not a great shot.”

“Fine.” Buck squatted, frowning into the water. “But I can write my own damn history paper. If mine’s bigger, you have to swim in there.”

“Are you kidding? That water’s gross. It’s, like, toxic from pollution. Anything could be in there. Snakes, or worse . . . the Backwater Beast. My mother said—”

“Your mother said?”

Milo kicked a log; it was rotten, and half a dozen centipedes scurried out of the gaping hole in the bark. He blanched and stumbled back, already trying to think of an excuse so Buck wouldn’t call him a coward, but just as he started to lose his balance he felt an almighty tug on the line. He held on, leveraging himself with his own unbalanced weight as the line went taut.

“Hold tight,” said Buck. “Looks like we got a live one.”

It was all Milo could do to hang on. The line swept left, around, and right again, pulling to its limit. The rod bowed as in prayer.

“What are you waiting for? Reel her in!”

He wiped his sweaty palm on his jeans and grabbed the handle, tried to crank it—but it wouldn’t budge. The thing in the water swam left and right, trying to pull away. Holding on with two hands, Milo watched the water’s susurrations as it parted for the line, and the thing below, and he saw a dark shape bigger than any fish he’d ever caught.

“Holy bejesus,” said Buck, gleaming with excitement. “Would you look at the size of that thing!”

For another fifteen minutes, Milo tried unsuccessfully to reel it in, but the thing was too strong; each time he pulled it halfway to the bank, it made a bid for freedom and the line unwound with a sound like a zipper.

Buck snickered as he watched. “How’s it going, Nancy?”

“You want to do it?”

Buck’s laughter died. He shook his head. “It’s your rod.” They watched the dark shape swim in lazy circles, opaque as a riddle.

“I think I’d better just let it go,” Milo said at last.

“How? It’s hooked good. You got anything to cut the line, or you want to toss the whole rod?”

“I like this rod.”

The sun started to angle through the trees, making the air green, the water green, the whole river’s edge smell green as summer. Buck put down his own rod, which nothing was biting, picked up a few small stones and tried skipping them. Only one bounced, making a ripple of concentric circles, before it slipped away. As he turned to get more rocks, Milo saw the side of his face that he had kept hidden. Black bruises muddied his cheek and jaw; the lid of his eye was swollen pink, turning to purple. Milo looked away quickly. He didn’t want to stare.

“Your dad at it again?” he asked.

Buck hesitated, his shoulders tensed. He threw the stones. Two skipped. “Only when he’s drinking.”

The dark shape wasn’t pulling anymore now that Milo had stopped trying to reel it in. He wedged his rod in the crevice of a log and levered it with a pile of rocks, then walked back through the trees.

“Giving up?” Buck called out.

“Taking a piss.”

He liked to play a game when peeing in the woods: target shooting. He aimed for an anthill, then directed the stream toward the erupted root of a hackberry that formed a twisted arch. As he went, he splashed over a glass bottle, rinsing the dirt away. It had once contained Old Crow bourbon whiskey, but now it was empty, with only a few brown dregs sitting at the bottom.

He finished up and came back, picked up his rod. But he didn’t dare try again to reel it in. “So what do I do?”

“I’ll tell you what.” Buck stood up. “Whatever it is, it knows it’s hooked. It’ll keep trying to swim free. Let it tire itself out. Then, when it’s got no fight left, reel it in.” His eyes didn’t leave the green water, and his voice was hard. He chucked the rest of his rocks into the water, not even trying to skip them. They sank.

They sat in the mud, leaning back against logs to watch the dark shape swim back and forth, like a tiger pacing in its cage.

“Maybe it’s a bull shark,” said Milo. “I heard they can swim up the Mississippi as far as Illinois.”

“Sounds like bullshit.” Buck uprooted a cattail and chewed the green stem. “I bet it’s a sturgeon.”

“What if it’s the Backwater Beast?”

“Come on. That’s just a scary story people tell gullible kids.”

Milo wanted to believe him, but he couldn’t help imagining whatever lurked beneath the water: its tentacles like electric eels, its eyes vast, lidless, staring with alien intelligence from the starry depths of its black pupils. Dragging his line back and forth. Letting him think it was the prey.

“Mr. Hindes thinks it’s real. He saw it.”

“Mr. Hindes also says he was abducted by aliens.” Buck put on his best impression of their gym teacher, giving himself a slight lisp. “‘Boys, you never know when you’ll be in a situation where you’ll need to run. If your mile time is over eight minutes, you won’t be able to outrun a bear . . . or a UFO. Three laps. Now!’”

“Remember when your dad found out about all that UFO stuff and came to the school he was so mad?” Milo laughed. “Said Mr. Hindes was putting ‘notions’ in our heads. Notions!”

Buck fiddled with his rod. “He almost beat up Mr. Hindes.”

“Isn’t he banned from the school grounds now?”

Buck nodded. “Yeah. Not that it matters. I’ve always walked.”

Even when Buck came the two miles to Milo’s house, he walked. His dad wouldn’t drive him. Said it built character. But you could always hear Buck’s dad coming; the rusted pickup squealed like a mechanical pig whenever it pulled into the parking lot of the liquor store.

“You’re lucky your dad left when you were a kid,” said Buck.

Milo didn’t see it that way, but he kept quiet.

Dusk bled sunlight from the trees. The sky purpled as the light glared slantways, throwing shadows. Dinner would be on soon, but Milo wasn’t all that hungry, especially not for his mother’s meatloaf, which even the richest ketchup couldn’t save.

“Bet it’s a sturgeon,” Buck said again. “Can you imagine the look on Trina McCalley’s face if you brought it to school on Monday? She’d suck your dick in an instant.”

“Gross,” said Milo. “You think?”

“Better bag the sucker and find out.”

Milo fingered the reel but was filled with foreboding. “Catch and release, though. Right?” Whatever it was, he wasn’t sure he even wanted to see it. The thought of the Backwater Beast’s round vapid eye rising out of the water stilled his hand. He licked his lips. “Maybe we better let it tire itself out a little longer. Wait ’til it’s real good and worn-out.”

“Getting dark,” said Buck. “If you want to give up, that’s okay. But you’d better strip down and get ready to swim.”

“I’m not going in there with that thing! And . . . who knows what else?”

“Come on. There’s nothing in that river that’ll hurt you.” Buck turned to him, his bruised face stark and livid in the failing light. He seemed angry. “There’s fish. There’s dead things. What are they gonna do to you, huh? You think some made-up monster’s gonna come up and, what, bite off your head? What use is there being scared of shit that isn’t real?” He kicked the rotten log, again and again, until it started to collapse. “The Backwater Beast is nothing. Nothing.”

Milo sucked in his lips, afraid to say anything. Afraid of the dark shape roving through the gloomy green water, the shadows falling in the trees behind him, the look in his friend’s eyes. Thrilled and afraid of mysterious things, of unknown possibilities. He’d never faced a real physical threat before. But the dangers lurking in the dark, what could be—that made the back of his neck prickle, like eyes were watching him from behind.

Locusts took up their calls in the trees, rising and falling as the wind shushed through the leaf-laden branches. They were plunging into night, now. Stars blinked to life in the darkening sky.

“So what. You’re not afraid of anything,” Milo said, trying not to feel the pull of envy.

Buck’s face soured. He reeled in his unbitten hook, the dead worm dangling, limp, skewered. He pulled it off, tossed it away. “We should get home. It’s late.”

“Not like your old man’s even going to notice. He’s probably passed out by now.”

Buck said nothing for a long moment. They listened to the crickets chirp.

“I just want to get home,” Buck said at last. “My mom will be waiting. Won’t yours?”

“Yeah, but she always tells me not to stay out late, and I always do, and all she ever does is tell me off and send me to bed.”

Buck’s eyes shined in the moonlight. It looked like he was going to cry, and Milo looked away, embarrassed for him. He’d only seen Buck cry twice: once when his wrist was broken, his hand bent at the wrong angle, and the other when he was hit so hard he lost a tooth. But he wasn’t scared of anything: not Simon’s bullying at school, not the haunted shack out in the woods where it was said a serial killer had chained up his victims, not monsters in the river or disease or infections from rusty nails or poison ivy or the dark.

But then, why would he be afraid of those things? They didn’t hurt him. His imagination didn’t have anywhere to run, not like Milo’s.

“You gonna reel that in, or what?”

Milo took a few breaths, steadying his hands. He could hardly see the shape anymore in the dark, but he could feel its heft on the end of the line.

“You know, I wish I did have a dad. To go fishing with. He could probably haul this in for us,” Milo admitted. He was scrawny, too tall. Someone bigger could bring in the Backwater Beast. Trina McCalley had never even looked at him.

“Bet my dad could’ve, if we’d hooked it a few hours ago.”

“What? Your dad was here?” Buck nodded. “When?”

“Before you got here.”

Milo started reeling it in. He put all his effort into cranking, digging his feet into the soft bank. His shoe hit another beer can, and he kicked it out of the way, getting better purchase on the earth. Pulled and cranked.

Slowly, the shape drifted closer.

Buck’s fresh bruise made more sense now. “What happened?” Milo asked, huffing as he struggled with the rod.

The water made a soft gulping sound as the creature was dragged in.

“I did a bad thing,” Buck said.

It was almost here. He almost had it. Distracted by his catch, Milo only distantly heard his friend. “What?”

“I didn’t know what else to do,” Buck said.

The shape started to emerge from the water.

Something hairy. Rounded. It rose from the black surface, revealing two white gummy eyes, a nose. An open crevice in the forehead, the skull cracked down the middle, washed of blood. The flesh bloating, waterlogged, pale as a fish.

“Buck . . .” Milo froze, unable to pull the body further out of the water. It stared at them with its dead, engorged eyes. His friend looked on, grim and tight-lipped. He wondered at first why Buck wasn’t surprised, and then he understood. It was what Buck had been trying to tell him.

The hook went up into the roof of the mouth, pulling its mouth open as the head tilted up out of the water.

“You won’t tell anyone,” said Buck, and it was almost a question, almost worried, and Milo felt his stomach flip that his best friend could even ask him that. Could doubt his friendship. But then, he thought, feeling much older here in the moonlight, of course Buck doubted. He didn’t know trust, not like Milo, who found himself longing for his mother’s overdone meatloaf.

“Catch and release,” he said.

Breathing slowly through his nose, Milo reeled the body halfway onto the bank, its legs still underwater. Before he could let himself think about it, he pried open the jaws, the flesh too-soft and gelid. The smell of water-rot exhaled from the open mouth. He yanked the hook free, imagining the corpse biting down on it and swimming, around and around, while its flesh swelled and fish pecked curiously at its eyes, its jaw grinning around the hook, refusing to sink.

Milo put one foot on the corpse’s shoulder and pushed the body back into the water. Buck’s father floated for a moment, then slipped out of sight.

“It’s okay,” Milo said. “He’s gone.”

They packed up their rods and prepared to head out through the trees.

“Hey, Buck?”

“Yeah.”

“I don’t think there is such a thing as the Backwater Beast.”

Buck looked at him. “There is,” he said. “We just caught him.”