It’s been three years since BMO brought us along on one final adventure through the Land of Ooo in the original series finale of “Adventure Time.” Three years since the Great Gum War, since Shermy and Beth, since the song that saved them all. Dang, dude.

But then HBO Max and Cartoon Network announced “Distant Lands,” a limited-run epilogue series of four hour-long specials that could make the adventures last just a little bit longer. And adventure we did, with a robot prequel, a relationship sequel and an unexpected vision of the future where our heroes Finn and Jake have finally kicked the bucket.

Oddly enough, though, all three specials released so far have dealt entirely with brand-new stories we could never have predicted from the way the original series ended. Of course, we knew that a) BMO had to have some origin story, b) Marceline and Princess Bubblegum would continue growing closer and c) Finn and Jake weren’t immortal. But none of these episodes grew from existing plot arcs; they simply drew on characters and plotlines from the original series to give us more context.

This is where “Wizard City,” the fourth and final special episode released Sept. 3, breaks new ground: it picks up right where a seemingly inconsequential thread left off in the finale. During the final battle, loyal Candy Kingdom resident and dark magic expert Peppermint Butler (voiced by Steve Little) got splashed with a serum that de-aged him back into a child and thus erased his knowledge of the mystic arts.

We know Peps isn’t one to take this sitting down, and “Wizard City” confirms his intentions: he’s heading back to wizard school to become a master of the dark arts yet again. This means that—of the four—the new special feels the most like a classic episode, as the main villain(s) ends up being none other than the dark wizard cult of Coconteppi, a monstrous cosmic entity on the same level as Orgalorg and the Lich.

Let’s regroup. We’ve got high school popularity contest tropes, dark mystery cult tropes and haunted-by-the-past tropes—all of which I’d normally be wary about. But this is “Adventure Time,” and this is Wizard City, so of course, they all work.

First up: Wiz Arts. No way can I talk about high school tropes in “Wizard City” without first shining a spotlight on my new favorite character—Cadebra (voiced by Chloe Coleman). The niece of wizard weirdo Abracadaniel, Cadebra prefers the funky flair of stage magic and illusions to actual spells, so she falls neatly into our outcast archetype, as her family naturally doesn’t approve of this choice.

Despite the inherent predictability of this kind of character, Cadebra is a treat. She’s perpetually followed by sparkles, refuses to stop making hilarious faces when confronted with literally anything and is just all-around endearing in every way. This makes her the perfect foil character to young Pep (voiced by Mace Montgomery Miskel), who brought all the rage and angst from his past life with him into his new diminutive form. They’re like “two toasts in a toaster,” Cadebra tells him. Not peas. Take notes, creative writing majors.

Teacher tropes abound as well, especially in the fantastic new character of Dr. Caledonius, who adds balance to our already whimsical cast of wizard professors. Compared to returning wizards like Bufo, Ron James and the Life-Giving Magus, Dr. Caledonius (voiced by Toks Olagundoye) is a boatload of fun in both her character design and personality. With her butterfly-shaped hair, huge round glasses and fanciful accent, she’s the epitome of the mentor/teacher/friend archetype, with a little bit of “maybe I’m suspicious because she’s too nice” thrown in for good measure.

Partially thanks to Dr. C’s mentorship, Pep eventually warms up to Cadebra, and the two social rejects develop an adorable pal dynamic that’s a necessary contrast to the surprisingly dark content of the episode’s main conflict. I know I tend to throw the word “dark” around a little too often, but this time, I mean it—an evil cult literally murders a student before we even get to the final showdown.

Which brings us to door number two: cult tropes. It’s clear from Pep’s first day at wizard school that the secret society of dark wizards (of which Ice King was once a part) is still very much active beneath the heart of Wizard City. As such, we’re not surprised when Bufo makes strange entrances and exits and randomly blurts out familiar incantations—but the anxiety and tension remains. We know there’s a cult; we just don’t know what they’re doing. And we know Pep is involved somehow, but not actually our Pep, because the ghastly, misguided spirit of the original Peppermint Butler haunts New Pep and is actually the one involved instead … it’s a lot.

Here we open door three, behind which Pep is haunted by his uncertain history. From the beginning of the episode, we’re forced to wonder: what happened to Peppermint Butler’s mind when his body reverted to that of a child? The answer is more complicated than even Pep himself can explain, involving self-inflicted curses and betrayal, among other things.

The confusion of this identity crisis is the episode’s best-executed concept, delivered to us at an emotional crux that sees Cadebra asking Pep if he’s trying to escape his “dark past.” Rejecting the trope, Pep instead tells Cadebra that he’s trying to recreate it, at the aggressive insistence of the specter tormenting him. When we realize Pep has been trying to push back against Peppermint Butler and re-master the magic arts on his own terms, it revitalizes the tired cliché and transforms the episode into more than a tale of a dark character with an even darker past. Instead, it becomes the story of Pep’s internal struggle to make sense of the two identities occupying his one body.

His internal conflict becomes external in the episode’s final act, when Dr. Caledonius is revealed to be the leader of the Coconteppi cult (but we knew that), and Pep must rely on Cadebra to—of course—show him what it means to be a friend. For a moment, we can ignore the fact that we literally watched a child die on screen to appreciate the sincerity of a young wizard (okay, stage magician) with a pure, righteous heart who just wants to help her new friend write his own future.

Because that’s what “Adventure Time” was always about—staying righteous in the face of evil. Not virtuous, noble, fearless or any of those other complexly heroic terms. Simply: righteous. With Cadebra by his side, I think Pep can make that promise.

And so will Fionna and Cake, when we hop back into Ooo yet again for a brand-new spin-off series featuring the gender-bent versions of the original series’ heroes. Because the adventure is never truly over. Mathematical!

“Adventure Time: Distant Lands” is now available to stream on HBO Max. Log in with Xfinity on Campus for students.