Mrs. Beakly and Launchpad have taken the children and Lena to see scary movie on Lena's (misleading) recommendation. However, instead of scaring any of the children, they are either excited or bored from a lack of production quality. Webby tries to defend the movie by it being "based on an actual true novel", while Huey says the only resource he trusts absolutely is the Junior Woodchuck Handbook. Webby rhymes off a bunch of seemingly fictional creatures like Were-ducks, Tri-clopes and Terrafirmians. While Huey refutes them all, Webby defends the existance of the Terrafirmians. Lena suggests they go investigate, and sneak off down a subway tunnel while Mrs. Beakley is distracted by Launchpad, who believes the "mole monsters" seen in the movie are real and gets a freak-out.
Once in the tunnel, Lena finds a barred-off subway tunnel that is "closed for renovations", but Webby claims is inhabited by a bunch of Terrafirmians. As they go in past the barricade, the tunnels rumble a bit, which Huey passes off as passing subway trains. Webby recounts the supposed history of the Terrafirmians, but Huey tries to explain it off with science. In fact, Huey is more interested in rock samples than potential monsters.
Lena screams to lure Webby and Huey over to an abandoned train, where she sets up a prank for them. While Webby appreciates the joke, Huey is annoyed and just wants to leave. Just before he leaves, however, a large shadow barges into the car. It turns out it was just Mrs. Beakley and the others, coming in after them once noticing they were missing.
Shortly thereafter, rumbling occurs and a rockfall blocks them from leaving down the tunnel they came. Mrs. Beakley suggests Launchpad tries to start the train moving, while she and Lena uncouple the last car that is buried in rubble. Once out of the car, Beakley threatens Lena from ever seeing Webby again. Because of this, Lena is very reluctant to help until she sees how much Beakley is struggling.
Rocks keep falling from above, strong enough to leave dents in the subway car's roof. Webby excitedly climbs up, thinking it's a Terrafirmian, but sees it is just a rock. Despite this, Webby refuses to give up on her belief that Terrafirmians still exist.
Launchpad, having convinced himself that Dewey is a mole monster and freaked out by the noises in the tunnel, freaks out and start the train up without consulting any of the others. A frantic progression down the tunnel leads them far away from where they were, but crashed the train further down. Dewey finally confronts Launchpad of his fear and points out that with his insane logic, Launchpad himself could be a mole monster. Launchpad denies it... which is exactly what a mole monster would say. Thus Launchpad must be an evil mole monster, but he knows he's not evil. Thus, maybe mole monsters aren't evil.
Because of the crash, Mrs. Beakley was trapped under one of the cars, unconscious. Despite Magica's shadow form trying to convince her to just leave Beakley, especially since she was so suspicious all this time, Lena uses her magical amulet to help rescue her.
Huey has a brief freak-out, not wanting to leave from a dangerous situation because he's in the light. Webby and Louie help him deal with the unknown and feel safe enough to venture out of the doomed car.
Everyone meets up together, relieved they are all safe, and find a beam of light shining from above. Huey, excited to have found a way out, rushes towards the light before the Terrafirmians cut them all off. However, as they entered the light, they see they aren't so scary, and in fact might have been just as scared of the ducks as the reverse. Huey and the lead Terrafirmian have a brief exchange, then the Terrafirmian break an exit for the ducks.
Beakley quiftly cures Launchpad of his delusion by confidently stating he's not a mole monster, then apologises to Lena by way of inviting her to the mansion. Lena assures Magica this was all of her plan to get close to the children and their long term goal.
- Absentee Actor: Scrooge and Donald are absent for the entire episode.
- Actor Allusion:
- Huey's criticism of the horror movie shower scene on the grounds of how unrealistic it is, because the monster would gain no traction in the wet shower, calls to mind Abed's breakdown of horror tropes and attempt to construct a purely logical horror story.
- More of a Production Team Allusion, but Huey's reliance on the Guidebook and his additional annotations as he learns more about the world are strongly reminiscent of Dipper Pines — even if Huey is Agent Scully instead of Agent Mulder.
- Adaptation Personality Change: While not precisely evil, the Terra-firmians in the 1987 series and the original Carl Barks story were massive jerks who couldn't care less about the destruction their Games caused. The only thing at all frightening about these Terra-firmians is how they look in the dark.
- Adult Fear:
- Because Beakley was helping Launchpad with his phobia of mole people, she's distracted long enough for Lena to take Webby and Huey down to the subway, and going down the abandoned tracks. Unsurprisingly, she chews out Lena for endangering everyone with her recklessness.
- The train crash and the structural collapses in the subways are very real dangers, in direct contrast to the series' usual cartoony perils of demons, ghosts, evil robots, and monsters. Especially as Mrs. Beakley was trapped unconsious underneath a subway car after the crash and most likely would have died if Lena didn't use her magic to save her.
- Aesop Amnesia: After the adventure is done with, it seems that Huey has learned that just because something is unknown and not in his guidebook doesn't mean it's scary. Cue Huey frantically writing about the Terra-firmians in the guidebook before declaring them not mysterious.
- Anger Born of Worry: The minute she finds Webby, Lena, and Huey, Mrs. Beakley chews them out for going into a dangerous place.
- Arbitrary Skepticism: Huey refuses to believe in the Terra-Firmians because they're not in the Junior Woodchuck guidebook. As lampshaded in the episode, this is despite the fact that he's visited Atlantis and fought a ghost pirate (and that those things are only in the guidebook because Huey added them himself). To be fair, the movie that got him started on this had logical inconsistencies he was complaining about (like attacking someone in the shower) and he may have just been a bit stubborn.
- Armor-Piercing Question:
Lena: So what does that make me?
- Lena delivers one to Beakley after the latter told Lena that Webby and the boys were "good kids with bright futures".
- Before that, Mrs. Beakley asks Lena "Who raised you, anyway?" While Lena doesn't respond, it's clear on her face that that question hit a nerve.
- When Launchpad's paranoia about anybody being a mole monster starts endangering everybody, a frustrated Dewey asks "By that logic, how do you know you're not a mole monster?" While this makes Launchpad start thinking he is a mole monster, it does stop his paranoia.
- Badass in Distress: Beakley is an incredibly strong and tough duck, but even she cannot protect herself from a train car falling on her. Lena's magic is the only thing that saves her.
- Because You Were Nice to Me: A variant. Lena saves Mrs. Beakley, not because she's been "nice" to her (in fact, they have a mutual dislike for each other), but because she's the first adult in a long time who's taken a sincere interest in making sure she turns out right.
- Black Comedy: Launchpad's mistrust of Dewey's goes as far as a joke about potentially killing him with a pipe.
- Cannot Tell Fiction from Reality: After seeing a horror movie about mole monsters, Launchpad spends the entire episode worrying that one of his friends is a mole monster in disguise, not realizing that the film's plot is entirely fictional.
- Captain Crash: Launchpad seems to have trouble with the idea of not crashing a vehicle he's driving.
- Character Focus:
- The first episode in the series, at least based on airing order, to focus on Huey, giving a real sense of his character, his flaws, and his quirks, when before he was Satellite Character to Louie, Webby, and Dewey. In particular, this is his first chance to really interact with Webby and show their dynamic together.
- Lena also gets a lot of focus as we see her use magic, interact with her Aunt and even get a What You Are in the Dark moment.
- Continuity Nod: When Webby asks Huey whether all the supernatural things they encountered with Scrooge McDuck are in the Junior Woodchuck Guidebook, she specifically mentions the Headless Man-Horse from the pilot episode. As Huey shows Webby that he adds anything new they encounter to the Guidebook, there's a drawing of the Medusa Gauntlet, Pixiu and his Gong, Captain Peghook and the Deus Excalibur, also from the pilot.
- Darker and Edgier:
- While still having a bright and colourful atmosphere, this episode is a lot more emotional, with all of the kids getting emotionally pushed to their limits. Furthermore, we get a real sense of Lena as a Byronic Hero, with her Conflicting Loyalties between her evil Aunt Magica and her friendship with Webby and the boys. Also, that train crash will make you cringe in worry and fear for the characters.
- The danger caused by structural collapse and the train crash in an underground subway are very real dangers that could happen to anyone. This is in direct contrast to the series' usual larger-than-life perils about curses, ghosts, demons and monsters, which are far more far-fetched and cartoony.
- Does Not Know His Own Strength: Implied with the Terra-firmians, who cause a lot of unintentional damage to the metro car when chasing the ducks, simply because of their sheer bulk.
- Do Wrong, Right: They're trying to escape a caved-in tunnel, but Lena sighing and saying "If you're gonna vandalize, at least do it right" suggests this is on her mind.
- Face Palm: Dewey does this in response to Launchpad's idiocy, after Launchpad believes that the metro lights burning Dewey's eyes is the evidence that Dewey's a mole monster in disguise.
- Faeries Don't Believe in Humans, Either: The Terra-firmians apparently viewed "billed creatures in the land above" as a myth or legend. "I told you they were real!"
- The movie the gang watches in the beginning of the episode is about mole monsters, foreshadowing that they will encounter another type of underground monsters (the Terra-firmians) in the episode.
- If you look closely, the first time Huey bumps into a Terra-Firmian, the Terra-Firmian reacts in the same way as Huey, screaming in fright in reaction to Huey's scream, showing that they are freaking out just as much over the ducks.
- One explanation Huey gives to the mysterious disappearance of a rock is that it vanished in a "sudden wormhole", which foreshadows a major plot point in "The Impossible Summit of Mount Neverrest!".note
- Freudian Trio:
- Id: Webby, who believes in the possible existence of Terra-firmians even without proof.
- Superego: Huey, who will not accept such claims unless he has solid proof - and also gets scared stiff when confronted with his fears of the unknown.
- Ego: Lena, who wants to believe in the existence of Terra-firmians along with Webby, but points out that the younger duckling doesn't help her case by utilizing fanfiction as "evidence". Louie takes up the role of the Ego when Lena goes off with Mrs. Beakley in the second and third acts of the episode, playing peacemaker between Webby and Huey and acknowleging that both their beliefs are possible.
- Funny Background Event: In the old metro car, some of the posters are advertisements for Glomgold Industries.
- Glowing Eyes of Doom:
- Magica's Living Shadow has red, glowing eyes.
- Subverted by the Terra-Firmians: their eyes glow red in the dark, and they are built up as scary monsters over the course of the episode, but are revealed to be quite friendly in the end.
- Great Big Book of Everything: The Junior Woodchuck Guidebook, of course. Though unlike in the original series where the book was weirdly applicable to any situation, Huey admits that there are some things the book doesn't know about so he adds them himself.
- Halloween Episode: Deemed as one by Disney XD according to Frank Angones, despite having only a few Halloween-specific elementsnote , thus airing four spots earlier than production order intended, so that it can be aired all through October.
- Hero of Another Story: It's heavily implied that the Terra-Firmians are a bunch of kids from Terra-Firmian society who are having their own explorational adventure just like our main characters are.
- If You're So Evil, Eat This Kitten: Magica is quite eager to get blood on Lena's hands and is skeptical about her reluctance to kill and desire to save Beakley. Lena insists at the end that it was Pragmatic Villainy, but Magica is still skeptical about Lena's commitment if her expression is anything to go by.
- Insane Troll Logic:
- Launchpad's Tomato in the Mirror bit is a beautiful example.
- Huey isn't much better. "It only exists if it has an entry in the Junior Woodchuck's Guidebook, because if something isn't in the Guidebook I can add an entry for it."
- Irony: The movie the family watches at the beginning of the episode is, presumably, a PG-13 or R-rated horror film. The children either love it, are bored by it, or criticize its plot holes, but Launchpad, an adult, is utterly traumatized by it, believing the film's plot could happen in real life.
- It Runs in the Family: From his mother's side, Huey has apparently inherited his great-uncle's, grandfather's, grandmother's, and uncle's stubborn, argumentative nature, particularly with members of the opposite sex.
- Jerkass Has a Point: An unwitting point, at least. While Mrs. Beakley's suspicions of Lena cause her to act towards the girl in a way which is not entirely admirable, Lena actually is a bit of a Toxic Friend Influence on Webby and the others and, unbeknownst to them, is in league with one of Scrooge's deadliest enemies in some scheme that doubtless has none of their best interests in mind. Lena doesn't really help her case when she encourages Webby and Huey to explore the abandoned subway tracks, which nearly gets everyone killed. It's also suggested that Mrs. Beakley's unwitting implication that Lena is not "a good kid with a bright future" touches a nerve with Lena because of this, since she knows full well that Beakley has more of a point than she realizes.
- Jerkass Realization:
Mrs. Beakley: They're good kids with bright futures!Lena: So what does that make me?Mrs. Beakley: [taken aback realizes the implications of what she just said] ... I don't know.
- Mrs. Beakley is very hard on Lena throughout the episode since she believes she's a bad influence on the kids until this exchange when she realizes that Lena doesn't seem to have anybody looking out for her.
- It's implied Lena gets one when Beakley protects her from the impact of the train crash. Her expression screams My God, What Have I Done? and she lifts the car off Beakley long enough to save her.
- Kids Shouldn't Watch Horror Films: Inverted. After watching a horror movie about mole monsters, the children are either very entertained by the excessive violence in the movie, or overly critical about the various plot holes. However, Launchpad, one of the adults accompanying them, is utterly traumatized, believing that the movie depicted true events.
- Literal-Minded: Launchpad thinks a man-child is a kind of creature.
- Living Shadow: This episode shows that Magica can take control of Lena's shadow in order to communicate with her.
- Long Game: Referenced by Lena to Magica as justification for saving Beakley. Notably, Magica isn't happy regardless...
- Mama Bear: For all her contentions with Lena, Mrs. Beakley protects her when Launchpad accidentally starts up the old subway car and endangers them.
- Manchild: Beakley outright refers to Launchpad as one. Considering how he reacted to the movie, she's got a point. (Launchpad is completely terrified by this phrase, acting like it's yet another terrible monster — half-man, half-child.)
- Mole Men: The horror movie the family watched in the beginning of the episode was about these.
- Mood Whiplash: This episode juggles several plots, each of which has varying levels of comedy, action and drama.
- First, the A-plot with Webby discovering the existence of Terra-Firmians, and helping Huey get over his fear of the unknown. (Dramatic)
- Second, the B-plot with Lena and Mrs Beakley arguing about the former being a bad influence to the rest of the kids. Also, thanks to Launchpad, the two are stuck riding the train on the outside whilst it's moving, and they're thrown off when it crashes. In the wreckage, Lena gets tempted by her Aunt Magica to leave Mrs Beakley for dead. This subplot also showcases Lena utilizing her powers for the first time to rescue Mrs Beakley. Lena's arc in this episode concludes with her being welcome to Duck Manor anytime, and her telling Aunt Magica that they can use this to their advantage in the long run. (Action)
- Third, Launchpad suspects Dewey of being a Mole Monster, and spends most of the episode up until the end trying to expose Dewey - but obviously failing. (Comedic)
- No, You: When Huey dismisses the Terra-Firmians as "ridiculous", Webby retorts "You're ridiculous!"
- Nothing Is Scarier: The real reason that Huey is pulling a major case of Arbitrary Skepticism.
Louie: Oh, that's way creepier.
- At one point, mysterious lights appear at the end of the tunnel. While Huey and Webby argue over what they might be, the lights suddenly disappear, silencing them.
- "Not Important to This Episode" Camp: Scrooge and Donald are once again absent.
- Not So Different:
- Despite their constant arguing in this episode, the events that cause them to argue also reveal how similar Webby and Huey are - both love exploration and discovery (Huey of natural phenomena like earthquakes and rocks, Webby of the supernatural), and both keep a book where they write about their passions (except Huey writes about what he's discovered and Webby writes about what she imagines).
- The ending shows that the Terra-firmians see the ducks just as mysterious as the ducks see them. Furthermore, it's implied that the five Terra-firmians that chased the ducks are also a group of adventurous children, and their color scheme matches the clothes of the triplets, Webby and Lena. The red one and the purple one even have a conversation almost identical to the one Huey and Webby had earlier.
- Painting the Frost on Windows: Webby suggests that the Terra-Firmians are responsible for tectonic plates moving, a Mythology Gag to the original Carl Barks comics, in which their races caused earthquakes.
- Pass the Popcorn: A Running Gag in the episode comes from Louie having brought his popcorn with him on the adventure and his tendency to pull it out when things get interesting. He even admits that he refilled it on the way out.
- Power Glows: Lena's telekinesis.
- Pragmatic Villainy: Lena justifies saving Beakley as this to Magica, claiming that doing so made Beakley less suspisious of her. This does have some merit, because at the end Beakley allow Lena to visit McDuck Manor any time she wants.
- Properly Paranoid: Beakley is very suspicious and untrusting of Lena, and just knows she's up to no good. She's not wrong; even without the Magica plot and Lena being The Mole, Lena does endanger Webby and the nephews with her actions. Of course, Magica won't take any chances.
- Real After All: The Terra-firmians turn out to be quite real. Amusingly, the ducks are apparently just as mythical to the Terri-firmians, being referred to as the "bill-faced creatures from above" by them.
- Reasonable Authority Figure: While Beakley (rightly) doesn't trust Lena and plans on putting the kibosh on her visiting Webby, she spends a lot of the time trying very hard to understand her, and even protects her when Launchpad gets the train moving out of control. Beakley eventually relents after Lena saves her life, and even lets her come to the mansion for pancakes.
- Right for the Wrong Reasons: Beakley wants to keep Lena away from Webby and the nephews, stating that "these are good kids, with good futures." She's right that Lena is a threat to the McDuck family. But Beakley is concerned about Lena's generic rebellious nature, and knows nothing of Lena assisting Magica DeSpell with her plans against the McDuck family.
- Rock Monster: The Terra-firmians are large, boulder-like creatures that move around rolling. Whether they are made of rock or just resemble rocks is ambiguous, but their weight compared to their size (as evidenced by their impact on the metro car) implies the former.
- Romanticism Versus Enlightenment: Lena and Webby are Romantic, believing in the Urban Legend about the Terra-firmians while Huey is enlightened, being committed to rational and natural explanations, and having a strictly empirical view (hence the whole the Junior Woodchuck book is never wrong, because whatever is not in it, will be added inside it). This even applies to their reaction to the movie, both Webby and Lena love the gorefest while Huey points out the implausibility of the scenes and actions.
- She Knows Too Much: Magica wants Lena to eliminate Beakley because she's suspicious of her origins, and poses a real threat to her agenda.
- Shout-Out: Huey and the red Terra-firmian making contact by touching their fingers parodies the famous scene from E.T. the Extra-Terrestrial.
- Spot the Imposter: Launchpad's paranoia manifests itself as a very clumsy version of this, either by accusing others of being mole-monsters because they deny it, or trying to trick Dewey into saying how much sunlight hurts his beady mole-monster eyes. Eventually, when he thinks he's a mole-monster based on this trope, Beakley bluntly tells him he isn't, leaving no room for doubt in his mind.
- Suddenly Voiced: This is the first episode in which Magica speaks.
- Taking the Bullet: Beakley gets knocked out protecting Lena from the impact of the subway crash. It's implied that Lena saves her for this reason.
- Teeth-Clenched Teamwork: Magica and Lena turn out to this, arguing over their methods and seeming to have an argumentative relationship in general. Lena also doesn't react very well when Beakley asked who raised her.
- Thinking Out Loud: Launchpad does this without realizing it, which causes him to believe Dewey is reading his mind.
- This Is Reality: Dewey tries to explain to Launchpad McQuack that mole monsters are just in movies, while this is real life.
- Tomato in the Mirror: Parodied; when the paranoid Launchpad (who, after watching a creepy movie, believes anyone could be a mole monster) is told by Dewey that by his logic, he could be a mole monster. Launchpad agrees with this and decides to improve his "brethren's" reputation above ground.
- Troll: Louie zigzags between supporting Huey and Webby just because he finds the arguing more entertaining than the movie.
- Universal Driver's License: Beakley immediately tasks Launchpad to drive the subway train out of the tunnel without even bothering to ask if Launchpad can drive a train. He gets right to it.
- What You Are in the Dark: When Beakley gets trapped under a train car, Magica tries to convince Lena to leave her there, as she's only getting in the way of their plans. Lena instead saves her with her magic. Though when Magica confronts her about it, Lena passes it off as Pragmatic Villainy, since she knew that saving Beakley would get her to stop trying to separate her and Webby.
- It's worth noting, however, that she only claims this after Mrs. Beakley allows her to stick with Webby; as if she's trying to convince Magica of it more than anything else.
- "Where? Where?": Launchpad after Beakley calls him a man-child, thinking it's some kind of monster.