At the Fort Duckburg historical site, the quadruplets and Webby were listening to Mrs. Quackfaster, who was dressed in period clothing, tell the story of how Cornelius Coot, descendant of the Duck family, fended off the Beagle militia single-handedly and established Duckburg in its modern form, all in front of a statue of Cornelius, armed with a saber and flintlock pistol, standing atop several defeated Beagles.
"Coot stamped himself upon out history in a way few ever will." Quackfaster says.
"We'll see about that." Webby says to herself, Rebecca giving a 'what do you mean' look, overhearing it.
"As a special treat today, Coot's descendant, Della Duck, will sky write the letter 'C' to commemorate him."
"Just a 'C'?" Dewey asks.
"Uncle Scrooge charges by the letter." Louie explains. "I'm parched. You got any refreshments? Maybe some Pep?"
"In this village, we only have traditional victuals, saltwater jerky, and raw buttermilk." Quackfaster says as she somehow quickly changes costume and pours some for Louie, as Dewey goes to churn butter.
"Wow, I can't believe we're related to THE Cornelius Coot, founding father of modern Duckburg." Rebecca says as she looks up at the statue of her great, great, great grandfather.
"You didn't know?" Huey asks.
"No, Uncle Scrooge never mentioned it..." She admits.
"That's... troubling."
"But hey, at least I now know kicking Beagle Boy butt is part of Duck family tradition." She shrugs.
Huey then tries on a capotain as Dewey and Louie come over, bored. "This capotain isn't even itchy enough to be authentic. Let's see if we can fly with Mom."
"Sure we could go, unless we want to uncover the greatest mystery your mom never solved." Webby says as she stands atop the statue and pulls out a journal.
"Woah, is that?" Dewey asks.
"Della's old journal. She was searching for a top-secret family treasure from the non-McDuck side of your family. the Beagles weren't just after the fort, they were after the Golden Armory of Cornelius Coot." She hops down and goes to each of the bored boys. "Untold treasure." She says to Louie. "Undiscovered history." She says to Huey as she puts the Capotain back on his head. "Unparalleled adventure." She says to Dewey, who she gives the journal to, before taking the mug of buttermilk from Louie. "Della couldn't crack it, but we can." She takes a sip, only to spit it out disgusted.
"You, probably shouldn't drink that." Rebecca comments.
Meanwhile, Della is walking to the hangar to retrieve the plane as she adjusts her flight goggles.. "Ah, the perfect day. Just me, the open sky, the Cloud Slayer, and where's my plane?!" She panics, finding it gone.
"Right here, Ms. D." Launchpad says as he opens the hangar door, revealing the Cloud Slayer/Sun Chaser a complete wreck, Della gasping at the state it is in.
"And there, and a bit over there. Don't worry, the Sun Chaser has been through way worse than this."
"It has?" Della asks concerned, voice strained as she picks up the flight yolk.
"Yeah, we've been through hundreds, maybe thousands of crashes together. If this old girl could talk."
"Grrr..." Della starts to get upset, prepared to beat the moronic Launchpad with theyolk, but inhales to calm down. "Listen, L.P., I need to fly over Fort Duckberg in t-minus three hours."
"Don't worry. We can stitch this baby back together in no time. Just need to find Spinny Boy."
"Spinny boy?"
Then, one of the propellers falls out of a tree and between them.
"There he is."
Della gets out her phone and calls Ian. "Hey, Ian! Look uh, I'm going to need your help with something."
"Uh, right away Ms. Duck. I'll be there as soon as possible." Ian responds over the phone, Della glad someone competent will be helping.
"Webby, most historians consider this stuff to be a myth. Coot was a ghost with a golden armory. He was everywhere at once. All myths." Huey explains as Webby examines the statue's base.
"Yeah, and so are most of the things we go on adventures looking for on a regular basis. And yet we still find them. Webby may be onto something." Rebecca points out.
"Even so, everyone and their mother went looking for that treasure." Louie says.
"Correction: everyone and 'your' mother." Webby then runs over and grabs a shovel. "We solved some big mysteries before, but this, this is the one that could make us legends!" She says as she throws the shovel that Rebecca, Huey, and Dewey dodge, but it hits Louie right in the gut, the green sibling doubling over in pain.
"Okay that didn't sound good." Rebecca says as she checks on her youngest brother, feeling his abdomen to make sure nothing was ruptured.
...
Soon, the kids have set up an area to work out how to find the treasure, Huey having 'cordoned off' the area with a sign.
"Alright, where do we dig?" Desey asks excitedly as Webby looks through the journal.
"It says here, 'find the truth beneath the legend'. Hmm." Webby reads as she and Huey look at it.
"That's it, I'm digging!" Dewey says as he prepares to dig, smacking Louie in the face with the handle.
"Oh!" Louie spills his mug of buttermilk all over the statue's plaque. "Oh no, my delicious gloppy history treat." He says sarcastically as he kicks the now-empty mug.
"Shh. Listen." Webby says, as there hear the buttermilk seeping in behind the plaque and dripping.
"It's hollow." Rebecca says.
"There's something under here." Huey adds.
"Truth beneath the legend!" Webby exclaims as they all start to wipe away the buttermilk, and pull on the plaque.
Soon, it gives way, Webby and Rebecca leaning in with their phone lights, revealing...
"A secret tunnel!" Rebecca says as she and Webby pull out of the passage.
"Told you." Webby says to the others. "Now lets go!" She says as they climb in.
Back at the hangar...
"I did it. I found a photo of what the plane is supposed to look like so we can piece it together. Let's start from the corners." Launchpad says as he gives the photo to Della, who looks unconvinced.
Ian looks at Della, and holds up his tablet. "Don't worry, I got the schematics for this exact model. The internet really is something else."
Della nods as she tosses the photo aside, and the two join Launchpad.
Queue montage of them reassembling the plane, Ian bolting everything secure while Della fixes mistakes Launchpad makes, the latter being rather clumsy.
Della closes a hatch on one of the pontoons, and finds her hands rather sticky for some reason. "Ew, why is everything sticky?"
"I used to use superglue to assemble the plane, but it proved tricky. Now, I use gum." Launchpad says, the pontoon falling off because gun is not a proper construction material.
Ian is concerned. "I'll uh, get the bolts for that..."
"You do that." Della says, wondering why there is a hamster on a wheel.
Back in the tunnels under the statue...
Louie is the last one to climb down. "Cool. So, this is our tomb?" He asks, before Webby leads the way.
"Alright, let's go! Everyone feel around." Webby instructs.
"Okay, rocky, ooh, stony, pebbly, woah oh! Pointy, metal, gold? Nope. Rusty shovel. Gross."
"It's an arrow pointing ahead. We're on the right track. I'm coming for your treasure, Coot!" Webby says as she runs ahead and slams face-first into a moss wall. "Ugh! This wall, here, is not a wall. Coot must have made a decoy wall out of peat moss. Ingenious. All we have to do is push ever so slightly and-" She pushes on it and falls in, the kids trying to grab on but getting dragged down as well, landing at the bottom. "Take that, moss wall!"
Huey then removes a piece and licks it. "Hmm, it doesn't taste mossy enough to be moss. What is that texture?"
"Why would you lick that?" Rebecca asks, disgusted.
"Just relax, Louie. Think of all the stuff you're going to buy with the treasure, okay? An empire brothers ottoman, case of imported Pep Superior, an emerald studded hoodie." Louie says to himself.
Then, Dewey starts laughing.
"Do not laugh in the face of my danger!"
"I'm not. Huey's tickling me."
"No I'm not." Huey says.
"Yes, you- Webby, turn your phone light on."
"It IS on." Webby says.
"Well, I can't see a thing."
"What?" Webby turns around and shines her light on Dewey, revealing the cause. "Oh, dear."
Dewey has two massive spiders on his face, one over each eye.
The boys start freaking out, Dewey trying to pull the spiders off, Huey spitting a spider and some web out of his mouth, while Louie is paralyzed, covered in spiders and begging for help.
Rebecca, meanwhile, is rather calm, watching the debacle as a lone spider climbs onto her shoulder. "Wow. Good thing Mr. Boone isn't here. He absolutely HATES spiders. Wonder what he is doing now?" She says as she flicks the spider off her shoulder.
Back at the newly finished plane, Della finishing with touching up a new paint job, drawing a shark mouth on it.
"I can't believe the kids fly in this with him flying." Ian says up to Della, just as Launchpad comes over.
"Ah, she's smiling. Happy plane, happy flight. Ooh." Launchpad says as Della hops down from the scaffolding, right as he is about to touch the plane.
"Don't. Paint's still wet. Don't. I just detailed that. Don't. Because I, I don't want you near my plane at all. Sorry, it's not personal. It's just that." Della says, pushing Launchpad back. "You know you're a bad pilot, right? No only in the sense that you crash every time you fly, he he he. Look, maybe with a couple of lessons."
"That's it. I can be your co-pilot."
"What? Noooo."
"I should learn from the best, right?"
"How do I say yes without agreeing to this?"
"Yeah, best teacher ever!" Launchpad sing-songs.
"Oh no, don't do that. Don't, ugh, get on the plane." Della sighs as Launchpad gets on.
"New reason I hate flying, that." Ian remarks, realizing he has to ride with them to ensure the plane is working as per manufacturer standards.
Back in the cave...
Webby hops through the tunnel, closely followed by Rebecca, the boys behind her. "Hup hup hup hup. Nice try, Coot, but you'll never break us."
Louie is still freaking out over the spiders. "Ugh, uhgh, so many legs everywhere. Ugh, I want to go home." He says before pulling his hoodie up, dumping at least half a dozen spiders on his head. "Yahh, ehnn, ahh!"
"Relax you three, it's fine." Reecca waves off.
"Huh?" Webby finds a spider in her hair, getting it out and letting it free. "Aw." She then proceeds to crawl around the cave, looking for clues.
"Hey, is it me, or does she seem a little more 'Webby' than usual?"
"This is starting to feel less like a fun adventure thing and more like a-" Dewey says.
"'Dangerous obsession that kills us all' thing? Maybe we should head back." Huey finishes and admits.
"What?" Rebecca says, in disbelief her brothers are giving up.
"Yeah, this adventure's a bust." Dewey says.
"You know, Dewey, we should go. No sense getting distracted by riding this amazing mine cart." Webby reveals.
"I'm sorry, mine cart? This is the ultimate. Everybody in. We ride to Coot's gold!" Dewey says in a complete change on heart as he enters one.
"Aaahhh! Ha ha hah spiders! Ha ha gah! Ugh!" Big Time then runs by, covered in webs and spiders as he stumbles into the other minecart.
"Big Time? The Beagles are after the treasure again. Quit repeating yourself, history, you rascal. Let's roll!" Webby says as everyone hops in.
The minecart rolls down the rail... only to get stuck at the bottom due to the steep incline on the other side.
"Well, that's bunk. Hopefully Ian's having more fun." Rebecca comments as they have to push the minecarts uphill.
...
After a while, and after losing Big Time when he stumbled into a spider tunnel, they finally make it to what seems like the treasure, labeled 'Cornelius Coot Arms'.
"This is it, the Golden Armory." Webby announces.
"Treasure." Louie says.
"Adventure." Dewey says.
"Historical accuracy." Huey says.
"Hmm..." Rebecca ponders the sign, something not quite right as her enthusiasm is somewhat dashed by critical analysis.
All but Rebecca head in, Huey lights an old candle, and find what appears to be the treasure, the four in awe. "Ah! Ooh! Woo hoo, ahh!" Louie then dives in.
"We uncovered the legend. Proven we're worthy. We did what nobody else could do. We found-" Webby starts, when Louie surfaces.
"Bleh, corn?" Louie says, finding that what they thought was treasure was a pile of corn.
"What? No, no no no no I. Maybe the treasure is beneath the corn. Or, uh, maybe there's a further riddle, and you have to find the golden scythe of corn, or-" Webby stumbles.
"Cornelius Coot Farms." Rebecca interrupts, having looked at the sign the whole time and remembering history on Cornelius Coot, realized it was an old sign with the 'F' broken out.
"What?" The other four ask.
"It isn't 'Cornelius Coot Arms', it is 'Cornelius Coot Farms', the sign was just broken and put together to look like the former. He was a corn farmer, not a fighter." She completes, to which Webby is dumbfounded and in disbelief, as Huey finds a journal labeled 'Coot Farms Logbook', and flips through it.
"It's a blueprint. Coot's very own system for storing corn." Huey says as he lights up the room, revealing a bunch of corn silos. "Those weren't mine carts. They were corn carts. And those markers we found along the way were just farm tools." He explains, further verifying.
"So, Coot was just a boring non-adventuring farmer?" Dewey asks.
"And his treasure was dirty, smelly corn?" Louie asks.
"Mom must have realized and that is why she never found the Golden Armory. It never existed." Rebecca finishes.
"Worst treasure hunt ever!" Louie complains and leaves, followed by Dewey.
"Sorry, Webby. It's over. Let's go home." Huey suggests as he leaves, Rebecca patting Webby on the shoulder and guiding her out, to which Webby runs in front of the boys to stop them.
"No no no no no. I know there's more to this. It's, it's Coot's final test. If it's not real, then how did he save the fort? How did he stop the Beagles?" Webby asks.
"And how are you gonna get out of this alive?" Ma Beagle asks as she, Bouncer, and Burger get up behind Webby.
"Yeah!" Webby says, before realizing. "Oh."
"This is ironic." Rebecca says.
...
The kids are swiftly captured and hauled along by Bouncer, Ma Beagle ranting and denouncing the Coots, Ducks, and McDucks as 'frauds and cheats', ironic as her family has been nothing but criminals their entire existence.
Webby and Rebecca get free and start to harass the Beagles, Webby being defiant as the boys and Rebecca admit there isn't any treasure, and it is all corn.
Eventually, Rebecca and Webby get ready to fight Ma Beagle, when suddenly the Sun Chaser/Cloud Slayer busts through the hillside, knocking the boys free of Bouncer's grip.
Della then exits with Launchpad, yelling at him for crashing. "Ah, you madman! We almost died," She pants, "but we didn't... Weird."
"Della!" Webby calls out.
"Kids?!" Della returns.
"The Beagle Boys!" Louie points out.
Della then grabs some rope and proceeds to tie up the Beagle Boys, saving the kids.
"Um, did you just become the hero of this adventure by accident?" Huey asks.
"Leave it to Mom to make the lamest adventure ever awesome." Dewey says.
"Go Mom!" Louie says.
Then, Ian stumbles out of the plane and kisses the ground, relieved to have landed alive in any way.
"Mr. Boone?" The kids ask, confused.
"Your mother had me help rebuild the plane. Made me fly in it to make sure the systems were right." He says, panicked. "I am never flying again!" He exclaims as Rebecca pats him on the head.
Della then looks to the kids. "I thought you were at the fort."
"Webby led us down here and- wait, where is she?" Louie says.
"You guys stay here, and stay safe. I'll find her." Della then runs down the tunnel.
"Webby! Mom! Wait up!" Rebecca runs after the two, leaving the boys, Ian, and Launchpad alone with the restrained Beagles.
...
Back in the corn storage room, Rebecca and Della find Webby searching frantically for evidence of the treasure.
"There's got to be treasure here, or a clue, or something." Webby says to herself.
"Oh, easy, Webby." Della says, trying to calm the girl down and pull her off the desk.
"No, stop!" I can do it myself." Webby insists as Della's journal falls out of her bag.
"Woah, my old journal? Webby, what's going on here?" Della asks.
"I've gone on some adventures, but look at everything you did by the time you were my age. I could never stack up to the legend of you, but maybe if I could solve the one mystery you couldn't, the Golden Armory of Cornelious Coot. except that it's just corn. Corn! I dragged the boys and Rebecca all the way down here to find... corn. I, I accomplished... corn. I'm an imposter, just like Coot. He was no hero, and I'm no Della Duck." Webby explains, distraught as she sits.
"Oh Webby..." Rebecca puts a comforting arm around her honorary sister, sitting beside her.
Della then sits on the other side of Webby. "But you did accomplish something. You made it farther than anyone else has. You don't have to be me. You just have to be Webby. And you have your own way of doing things that is unique, and special. You don't have to prove yourself to anyone, and- oh boy. I should really apologize to Launchpad."
Then, a fuse they didn't notice was lit lights candles underneath the silos, causing the corn to start popping, sounding an awful lot like gunfire.
"Wait a minute..." Rebecca realizes.
Webby gasps. "Coot was like a ghost, he was everywhere, and nowhere. His musket fire came from all directions." She reiterates the story, putting the pieces together.
"What?" Della asks.
"This 'was' Coot's armory. He turned his corn into popcorn," Webby explains.
"And convinced the Beagles that he was an entire army." Rebecca adds.
"He beat them using his wits." The two say as one.
"Wow, I guess he was a hero in his own way."
Then, they hear Ma Beagle, and Ian, scream.
"That doesn't sound good." Rebecca says, noticing the room filling up. "And we should get out of here. RUN!"
The three book it out of the 'Armory', and back to the group, who have all been captured by Big Time, now going by Bug Time, and his spider army, who have wrapped the other 8 up in spider silk, Ian petrified with fear.
Della swiftly grabs a scythe and cuts the boys, Launchpad, and Ian free, Rebecca carrying the too-scared-to-move Ian into the plane just as a tidal wave of popcorn engulfs everything.
"We can't back up. There's no way out, unless we..." Della sighs. "Launchpad, do your thing."
"Nibbles, give me a boost. Everyone relax, we're about to crash." Launchpad says.
"That actually is comforting." Della admits as Launchpad crashes them out the other side of the mountain, to safety.
"Everyone okay?" Della asks.
"Me? I'm fine. Mr. Boone though..." Rebecca says as she looks to Ian, who is in the fetal position.
"Spiders. Spiders everywhere. They wanted to eat me. I don't wanna die..." Ian rocks back and forth, traumatized.
"He, REALLY, hates spiders." Rebecca says, rubbing his head as they fly off.