The golf cart screamed in agony as Dipper stamped his foot down desperately on the pedal, trying his best to bleed every bit of available power and speed out of the tumbledown plastic vehicle. The results were loud, uncomfortable and bumpy, the vehicle leaping over the slightest obstacle as it flew well beyond its recommended capabilities.

"C'mon, c'mon!" He yelled. "Why didn't Soos fit NOS to all of these damned things?!"

"Probably because the last one got destroyed by a goose," Mabel said. "Nobody wants their golf cart to be destroyed by a giant goose."

"Just keep your foot down!" Pacifica barked.

"I'm trying! I'm trying!"

"It's just a steam train, how fast can it be?" Mabel asked.

"Faster than a damned golf cart, Mabel!" Dipper retorted.

"Maybe there's too much weight on the cart?"

"Hey!" Pacifica snapped. "We aren't that-"

"I'll get off if you guys want?"

Pacifica and Dipper looked at eachother as the cart continued its tumultuous path, somewhat taken aback by Mabel's suggestion.

"You'd do that?"

"Guys, if this is important, I'd 100% do that. 1000% do that!"

"Mabel, I really appreciate it, but we don't really have time to stop-"

"Then you don't have to! Good luck, guys!" Mabel chirped, giving her brother a hug. "Don't do anything dumb!"

"Mabel - Mabel, wait!" Dipper protested. "You can't just-"

Mabel shot her Grappling hook and flew out of the golf cart, pulling herself up to a treetop and cheering for her brother as the golf cart picked up speed. "You can do it, bro-bro!"

"That was really dumb, Mabel!" Dipper yelled - but he was drowned out by the screaming of the golf cart as it finally topped out its maximum torque.

"If it helps, Dipper, surely it's a good thing your sister is safe."

"I- I guess, but-"

"Plus, if we need help, I can at least text her. Your Grunkles barely know how to unlock a cellphone, let alone use it."

"But-"

"Look! There it is!"

Dipper's jaw hung open. There it was, alright.

In the middle of the valley, the railroad stood - a fresh ribbon of steel and lumber in the landscape, nestled comfortably on pebbles and stones, surrounded by grass and wildflowers. The sun glinted from the rails and freshly tarred sleepers, picking out the shape of each pebble and granite stone underneath them.

More surprising though, was what stood alongside the log-cabin fueling stage. No.4-point-5 stood proudly as water was poured into her tender, a glistening, black locomotive with red wheels, adorned with brass and polished copper. A wisp of steam breathed from the rods and pipes that led to her wheels, capped off with a large headlight in front of her funnel, that gently released a swaying trail of soot and smoke.

"Whoa. It's kinda pretty." Pacifica whispered with a certain level of reverence.

"All the more reason to-"

BANG!

Whether they ran over a stray railroad spike, a sharp rock or a gnome, nobody could really say. In any sense, the golf cart spun out of control as the shredded remains of its leftmost driving tyre flew out behind the ensuing corkscrew.

Pacifica clung to Dipper, the two of them yelling in disarray as the screeching vehicle landed on its side, still frustratingly far from the locomotive they were intending to protect.

"Ugh… great driving, dork." She groaned, rubbing her head. "You okay?"

Dipper was too busy grabbing Pacifica's hand. "We gotta warn them!"

"Wait."

"Huh?"

Pacifica grabbed him, plunged her hands into his vest and leaned close, her hot breath burning against his chin as she held him tight. Dipper flushed and gulped, holding his breath, standing stiff as a board, waiting to see where this tense moment would-

The Northwest heir grabbed the whistle and the flags, and started blowing as hard as she could, waving the flags behind her as she took off running - leaving a very perturbed Dipper behind.

He - he must have imagined that. Right? Yeah, he totally imagined it.

"Hey! Hey, wait for me!" he yelled, following her as fast as he could.

The locomotive stood there, simmering contently, its valves and pipes sputtering little puffs of vapour as she slowly warmed her boiler in the morning sun. The engine's driver continued working, tapping gauges, twisting valves and spinning taps as they waited for the needle to finally rise to the pressure it needed.

It was satisfying, having something so solid and tactile to mess around with, to feel so much power, noise and kinetic energy under your grade-four steel-toe boots. Their overalls were already streaked in grease and soot, like a sort of christening to this new way of life.

They'd always figured they'd go into something mechanical. Something like fast cars, or tractors, or trucks - steam trains were not on the agenda, but they were absolutely overjoyed to be here. It felt natural - a great, big, dirty machine with a fire - that weighed the same as forty cars? Y'know, that was pretty cool.

The young engineer vaulted out of the cab with a grin to start loading up on coal from the chute, when they heard it. Two familiar faces ran down the hillside, blowing a guard's whistle and waving flags as as they descended frantically, coming stupidly close to tripping over their own legs with every rapid, desperate stride.

"Wait, is that-"

Regardless of the two teenager's desperate attempts to beat the clock, the driver continued with their routine. The chain was pulled, the hatch opened, and with a rumbling roar - one that threatened to drown out Dipper and Pacifica's shouts of warning - the dirty, sooty fuel was poured into the locomotive's tender.

"Oh no, nononon- Dipper, we're too late!" Pacifica yelled, grabbing his arm while panting for air.

The sudden movement was enough to make him lose his footing - and the Northwest heir rapidly followed. Together, they stumbled and slid down the hill, streaking down the grass, still trying to wave their flags and blow their whistles.

At last, they came to a halt at the foot of the locomotive's driving wheels. They were immediately in awe of the sheer size of the thing; a giant machine that seemed to breathe and spit hot water, smoke and fire - a big, cast iron creature. It felt almost as if it was a simmering steel dragon, eagerly waiting for its chance to take flight.

Considering what they had seen the Boggles do, they were somewhat worried that the dragon could, indeed, be very capable of laying waste to Gravity Falls. The nature of the engine became very sinister, with that in mind.

Dipper flinched as a wisp of hot steam released from its insides, his little pigeon chest still desperately clamouring for oxygen. "Jeez."

"I've never seen a steam train up close before," Pacifica whispered. "Are they always this big?"

"Sure are. This ain't even a big one." The engineer replied - in a particularly familiar voice.

Then, Dipper looked up - his jaw instantly hanging agape as the driver climbed back up the little stepladder into the cab.

Dipper blinked. There, in a pair of denim overalls and a stripy cap, was Wendy Corduroy - her long, red hair tucked behind her, a shovel strapped over her back as if it were a sword, her hands swathed in heavy-duty leather gloves. She put a hand on her hip and smirked at the sight of them, covered in grass stains, staring up at the locomotive's boiler, still puffing away like they'd just run a marathon.

"Hey, guys. You wanna take a look?"