Wendy was happy to be alive when the wind was in her hair. She patted the side of No.4-point-5 with pride as the steam engine's array of wheels and rods hammered beneath her feet. It was always easy returning to Gravity Falls - after all, coming down from the cliffs was almost entirely downhill.
The engine was newly rebuilt - thanks to McGucket's mechanical tinkering - and now carried some kind of ridiculous mechanical gizmo in order to prevent a repeat of the Boggle incident. Laden with solar panels, batteries and reservoirs, the engine was no longer a natural coal burner, though you'd be forgiven for thinking otherwise - thanks to McGucket's addition of a giant smoke machine deep in the engine's guts.
So there it was, still chuffing and puffing away, without nary a shovel.
She looked over to Marcus, who now solely had water to deal with - looking up gauges with an enthusiasm she rarely saw from him, and quietly reflected on the fact that everything seemed so good in the world. Sure, she'd love to spend more time with the Pines - but hell, she was growing up. She could order booze now. Provided she looked confident enough. And had a fake ID. And was talking to a shopkeeper who'd never met her before. Oh yes, sixteen was quite an age to be, and her seventeenth wasn't too far away.
Was this oily, mechanical venture her calling? She had a feeling it might be.
Innocent of the chaos that had taken place in town - and utterly unaware of their father's finest hour - Wendy and Marcus really didn't have any worries, save for the boiler pressure, the water and the fire. It was a remarkably simple, pleasant existence.
Of course, that innocence didn't last very long. In a bowl valley like that of Gravity Falls, water only had so many places to go. And right now, that was up.
"Hey, Wendy." Marcus said. "Check the track."
"Huh?"
"Just do it."
The lumberjack's daughter leant over the cab windows and blinked as water began slowly lapping at the wooden sleepers. She raised an eyebrow. "That's weird."
"Think we should stop?"
"Na, safest place is gonna be in the town." She replied, entirely nonplussed.
Behind the engine, a few rattling wagons of sand shook about. Some kind of quantum ballast stabiliser, according to McGucket. She had never really paid attention to the manifests, more to the fact she got the best views and the pride of having a giant 50-ton lump of metal in her hands. What more could any teenager want than that kind of responsibility? She could basically joyride in the biggest, toughest car she'd ever seen.
The engine's beat continued, though just as they reached the lowest extremities of the hill, it was punctuated by a sloshing noise. The locomotive was treading water.
"Damn. Marcus, heat her up, huh? We don't want it gettin' splashed out."
"Sure, Wendy. We could reverse up the hill?"
"Not with soaked wheels we can't, she'd never hold."
"Damn. Uh, alright." He huffed, twisting one of the McGucket-designed dials that were mounted in the cab. Authenticity be damned.
The engine accelerated gently as it was fed, the power in her sufficient to plough through the minor flood without too much trouble. It was perhaps a testament to the two and their relative inexperience that they never even considered the idea of the track being damaged.
Under the water line, disturbed by thundering pistons and rods, the locomotive churned up a miniature whirlpool, dragging water towards it and spitting out as it continued trawling through the ever-increasing flood.
As the water rose, it collected lumps of debris and detritus. Spiked bludgeons from the town's famously dangerous litter, crates of long-expired Dinkies, even the odd gnome. The latter of which whacked against a lever by the track. Under the water, a dull clunk rang out as the rails switched over, leading to a worn old sidetrack and into the hillside.
When the town had rebuilt the Gravity Falls railroad, they had done a proper job of it. They were eager to maintain its fabric as much as they could - something the history buffs among them had insisted. If there was a switch, it was replaced or restored. Nothing was cut off. Nothing removed.
The engine screeched as it took the sharp corner, and cracked firmly against the roof of the obscured tunnel. The stone of the cliff slammed against the engine's smokestack, knocking back it back and rerouting the engine's thick artificial exhaust, which blew into the cab and threatened to blind them.
"Jeez!" Wendy coughed and gagged. "What the hell did McGucket use to build that thing?!"
"I can't see!" said Marcus, seemingly forgetting the fact he was usually blinded by his hair and beanie, anyway.
"Turn it off! Turn it off!" Wendy yelled.
"I just said I can't see!" he retorted.
The locomotive screeched into the caverns inside cliffs, while water flooded into the town's subterranean tunnels and drains. Wendy yelled as the locomotive bucked over uneven track, throwing her to the cab floor as it swayed wildly back and forth.
"Why can't we just have a normal damned day of work?!" She growled, forcing herself up and clutching hold of the windowframe as the rollercoaster continued unabated.
"D-do you think the town's okay with all that water?"
"I don't know, right now I think we probably have to count on us being okay!" She replied, once again trying the brake. "We gotta do something!"
Marcus looked around frantically and blew the whistle. Wendy just glared at him. "Sorry. All I could think of."
The erratic chuffing of the engine echoed across the subterranean tunnels, seemingly spiralling down in a constant, subtle loop. Closed switches and vein-like tunnels flew past them, wooden beams ever-so-slightly skimming the locomotive's upper extremities, scraping off the paint and grinding against iron so gently that it came off in thin, curled strips like planed plywood.
"We just gotta hope it leads out." Marcus huffed.
"Are you crazy?! You wanna keep going?!"
"Think about it, Wendy - we brake here, we ain't gonna get out - you saw the slope we just went down, and there's sure as hell no footpath."
She glanced out of the locomotive at the roaring tunnels, screeching shafts and sparking rails, the engine swaying wildly on its stiff iron chassis. Wendy had a terrible feeling that this experience would have felt very familiar to Dipper and Pacifica. The uncertainty, the turbulence, the ever-increasing desperation…
Though, at least there wasn't a fire this time. Just a bunch of lights, dials and switches, soundtracked by thundering pistons and puffing clouds. The Corduroy's only daughter narrowed her eyes as she tried to look ahead of the thundering iron horse, shading her eyes as best she could from artificial chemical smoke.
Marcus stumbled and grabbed the whistle cord - prompting the engine to let out a long, slow, almost mournful hooo-oooo-ooooot that seemed to echo across the caves louder than any other sound underneath the town's terrain.
And as deep-down as the sound was bellowing…
One ear heard it. An ear upon the rooftop. A rotten, gnarled, yellowed ear, filled with wax and self-assured loathing of his fellow man. That bearded, rotten beast rolled his shoulders… and smiled. Smiled so broadly that every pit, cavity and ulcer in his disgusting mouth was on show.