In the town of Round-Lake, the wind always carried a little excitement from the shore: horns answered each other; trams tinkled; and ships puffed fat, cheerful smoke rings over the water. Once a year, on Rolling Day, every machine, vehicle, and gadget could show what it could do. On the main square, colorful flags flapped; the smell of baked pretzels roamed the streets; and children competed to see who could imitate the ambulance siren loudest.

Lili stood in front of her grandfather's workshop and proudly patted the side of the greenish-blue, slender machine. Its name was Dragonfly—not because it pinched, but because it glided on the water as effortlessly as real dragonflies. Its rubber wheels could fold under its body; a shiny propeller whirred at the back; and in front, two big, round 'light-eyes' blinked in the sunlight. Inside, it smelled of freshly varnished wood. The instruments clicked-clacked if Lili touched the copper buttons. A tiny copper flower adorned the middle of the steering wheel.

– Today we show what you know, sweet Dragonfly – Lili stroked the steering wheel.

– And also what you know – winked Tobias, her grandfather, who was once a train driver and then grew fond of everything that clicked and puffed. Oil spots smiled on his forehead.

In the city, preparations were already rumbling. Red buses wore ribbons around their hips; a friendly concrete mixer held paper strips, mock confetti, in its driver's cab; and under the willow trees, an old tram practiced with bell ringing. Clacker, the freight locomotive arriving from the train station, blew a happily long "Tooot!" On the waterfront, Boom-Boom, the yellow loading crane, slowly lifted and lowered its huge hook, as if swinging in a race with the waves.

Then the trouble happened. Zsofi, the old ferry that carried the children's orchestra and the instrumentalists to the other side for the big opening, suddenly started coughing. It jerked once, grunted twice, then fell silent. On the water, on the other side of the plank that connected to the stage, stood the orchestra: violin cases, cellos, trumpets, sheet music stands—and a slightly nervous conductor, Aunt Aranka, who helplessly twirled her hat.

– They won't make it across in time! – shouted the mayor, Lajos Nagy, who wore a checkered megaphone around his neck. – Rolling Day opening without an orchestra? That's like pancakes without jam!

Lili looked around, then raised her hand. – Dragonfly will go for them!

Tobias nodded. – Sailor style, my captain.

Dragonfly rolled down the slipway elegantly. Its wheels splashed softly into the water, then disappeared into its belly like turtle legs. At its back, the propeller buzzed up: Vrooom, whooosh! The waves laughed around it, and Lili steered, while Tobias worked between the levers and pedals. Boom-Boom the crane rang his bell encouragingly, startling a few seagulls who fluttered up and circled in the sky.

On the water, every sound became different. The crow's screech sounded like a distant trumpet; the rustling of reeds, whispering cymbals. Lili watched the underwater moss through her small, periscope-like telescope—because Dragonfly even had one!—and noticed the swirling green stripes. The stone bridge under the mill sat low over the water, like a snoozing cat.

– Flag down, away with the mast! – waved Tobias.

Lili pressed a bronze button; the flagpole collapsed; Dragonfly huddled, and glided smoothly under the stone arch. On the other side, however, the propeller suddenly made a chirping sound.

– Seaweed! – said Lili, and already grabbed the long-handled hook. In water not even knee-deep, she didn't have an easy job, but from the side, through the trapdoor, she carefully reached in and peeled the green ribbons off the blades. The propeller sighed, as if freed from a scarf.

– Thank you, machinist – grinned Tobias, and Dragonfly's 'light-eye' seemed to blink appreciatively.

On the way, they met Meringue, the all-smiles bulldozer, who pushed the sandbank away from the shore, so small sailboats wouldn't get stuck.

– Road clear! – shouted Meringue, and saluted with the tip of his shovel.

At the railway embankment, Clacker puffed across, and Lili waited until the barrier rose. Loop, the smart robot policeman, stopped the cars at the bridgehead so Dragonfly could turn freely. Everyone waved: "Go!"

On the other side, the children cheered when they saw them. Aunt Aranka was relieved and tense at the same time.

– Where do I put the double bass? – asked a bespectacled boy.

– There, where Dragonfly is widest. I'll fold down the rear benches – said Lili. – Cellos here, trumpet players there, let's hold the sheet music against the wind. Strap, ring, buckle—we are ready.

The machine patiently tolerated being packed full. It didn't groan; it just nodded a little, as if counting how many legs, wheels, cases, and elbows sat inside it. A curious mallard jumped up on the stairs, then rather splashed back when the clarinet squeaked a note for a test.

– Rescue run starts! – reported Lili, and Dragonfly, buzzing, spun its propeller.

The way back was harder. The weight of the cargo pressed it deeper into the water; the waves made tiny grimaces on its side wall. Then, from close by, faint honking was heard. Buttercup, the spotted-nosed, nimble tugboat, carefully pulled alongside them.

– I'll help push – mumbled Buttercup in a deep voice.

– Thank you – nodded Lili, and attached a soft rope to the eye bolt on Dragonfly's back. Just so, for safety's sake, Buttercup nudged them three finger widths, and they slid easier.

From above, Stork–7, the white-red sports plane, circled enthusiastically; the pilot's glove waved from the window. The plane whooshed in a sharp turn over the shallow water, and Lili saw a bluish stripe in the water: the edge of the sandbank. Stork–7 showed the way with its movements, as if it were a ruler.

They reached the swing bridge that spanned the city canal. Loop's spotted arms spun; the bridge, creaking, readily slid aside. Clacker blew a short blast from the distance, like someone giving a beat: "Now... now!" Lili pushed the throttle gently forward, and Dragonfly jumped, then glided through the gap. On the shore, the concrete mixer tinkled, as if cups were knocked together.

The city hall clock started drumming out the minutes. One, two, three—counted Lili to herself. The cobblestones of the main square glittered from the fine spray of the sprinkler fire truck; the pretzel lady's hat stood askew from excitement.

– Ten more minutes until the opening! – shouted the mayor, but his voice already started laughing.

Dragonfly reached the ramp. The children, disciplined yet on dancing feet, jumped out. Aunt Aranka gripped her baton as if embracing it. The double bass floated majestically. Lili undid the straps; the tambourine players knocked two palm-sized drumsticks together: "Knock!"

– To our places! – said Aunt Aranka, and suddenly everyone knew what to do.

The city hall clock struck noon. Seriously, like a lion that doesn't roar, but just turns there. Aunt Aranka raised her baton; the violins smiled at the cellos; the drum shrugged its shoulder; and the first sound spoke. It started like when Dragonfly's propeller took a breath for the first time: gently, then more and more bravely, until finally the square filled with music, like the lake filling with water from a spring.

Boom-Boom the crane rang happily; the tram tinkled; Clacker blew; Buttercup honked; and Stork–7 tilted its wing. The city made music together with the orchestra. Lili looked back at Dragonfly, which rested on the edge of the ramp. Its 'light-eyes' blinked warm light, as if it were smiling too.

– Heroes! – said Mayor Lajos Nagy, and pinned a blue ribbon on Dragonfly's nose. – The ornament of Rolling Day!

– And the machinist – added Tobias, while he hung a tiny, bronze wrench around Lili's neck.

– Not even a machinist – laughed Lili – rather a friend. Dragonfly's friend.

Later, when the orchestra was already playing and the pretzels crunched between teeth, Lili and Tobias bent together over the hood of Zsofi, the ferry. A stubborn screw, a forgotten small filter—all little things, but together a big obstacle. Tobias adjusted patiently, Lili shone the light, and Zsofi finally rumbled happily to life.

The sun's light glittered on the water, and Dragonfly purred softly next to the ramp, as if saying: "Will we go tomorrow too?" Lili stroked the small copper flower of the steering wheel.

– Tomorrow too, and the day after too – she whispered. – Because with vehicles, the world is exactly as big as we can roll, push, pull, fly, and swim it.

Over the lake, a real dragonfly whooshed across, then disappeared into the reeds. And the town of Round-Lake lived and clicked on, full of friendship, screws, and surprises.