Thirty years ago this month, a landmark episode of The X-Files hit the airwaves: Humbug. A quirky twist on the shows established monster-of-the-week formula, it offered a proper introduction to scripter Darin Morgan, who soon became a fan favoriteand with that, showed that there was room for a sense of humor amid the shows conspiracy theories and supernatural horrors. Humbug debuted March 31, 1995, the 20th episode in the shows second season. Its nearly impossible to imagine in our current streaming era, but during The X-Files original run from 1993-2002, episode counts ranged from 20-25 per season, with season two topping out at 25. So by the time this entry rolled around, audiences had been entrenched in season two since September 1994s premiere, Little Green Men, an episode furthering the shows alien mythology written by futureFinal Destination duo Glen Morgan (Darins brother) and James Wong. Season two gave an early tease of Darin Morgans storytelling with its third episode, Blood, also co-written by Glen Morgan and Wong from a Darin Morgan story. Its a techno-horror tale involving subliminal messages and pesticide contamination; clever and shocking in its own way, but not the surprising tonal departure Humbug would prove to be. The episode kicks off with a misdirect: two boys splash around in a pool when a figure, framed as some kind of menacing threat, sneaks into the water with them. While hes a scary-looking dude, its the kids playful dad, and theyre delighted to see him. The camera pulls back to show signage letting us know this is the Alligator Man, building on the shows logline setting the episode in Gibsonton, Floridalong famed as a home base for circus and sideshow performers. In its opening moments, Humbug subverts the expected. The monster is instantly humanized as hes shown to be a loving fatherbut dont get too attached to him, because there is a monster in this episode, albeit a misunderstood one, and the Alligator Man is its latest victim.When Mulder and Scully appear on the scene, we learn the culprit may be a serial killer with a specific MO that causes a peculiar fatal wound; their body count hovers near 50, with seemingly randomly chosen victims found in nearly every state. While the FBI agents are puzzling through their latest bizarre case, the setting they find themselves in also subverts the expected. At the Alligator Mans funeral, attended by a bearded lady and several little peopleand eventually disrupted by Mr. Blockhead, a man who drives a spike into his chestScully and Mulder stand out by being so eye-catchingly ordinary. While theres a mystery afoot, in keeping with The X-Files monster-of-the-week formula, the setting is what makes Humbug truly inspired. It offers a peek into the real world of sideshow performers, handled way more sensitively than Tod Brownings 1932 film Freaks, but with similar themes of building community within what one character dubs very special people. Morgans script goes out of its way to explain why Gibsontown is so important to the people who live there, and how their experience grappling with their perceived othernesslike the Alligator Mans skin conditiongives them strength of character more often than it turns them into bloodthirsty maniacs. We also get some sideshow history in the tale of conjoined twins Chang and Eng, whose real-life story ends up mirroring the eventual Humbug killer.The episode has a lot of fun with Scully and Mulder being so out of placea familiar enough role for Scully, the confirmed skeptic, though she does fall for a carnival gag after dryly evoking P.T. Barnums line about a sucker being born every minute. Mulder latches onto a theory involving the mythological Fiji mermaid which even the townspeople chuckle at; Mulder is also made fun of for being almost too good looking. Most delightful is his banter with the acid-tongued proprietor of the mobile-home park where he and Scully rent temporary lodgings; the character is played by Michael J. Anderson, then immediately recognizable as Twin Peaks Man From Another Placemaking for a nifty post-Peaks reunion for Anderson and David Duchovny. Aside from simply being a part of The X-Files at the height of its fame, and that Twin Peaks wink, Humbug reaches back to another arena of 1990s nostalgia: Mr. Blockhead is played by Jim Rose, whose Jim Rose Circus toured as part of Lollapalooza, the eras most iconic music festival. The Enigma, who has a memorable turn in Humbug as the Conudrum, was also part of Roses show, and these two characters are used to point out the difference between people who are born with conditions that make them so-called freaks, vulnerable to exploitation by Barnum types, and people who create and cultivate those qualities voluntarily. Though Humbug is ultimately rather dark, finding its way to a conclusion that literally proves the phrase its whats inside that counts, its moments of weird levity still make it a delight: Mulder declaring a bed of nails more comfortable than a futon, Scully pretending to eat a bug in front of the obnoxiously shocking Mr. Blockhead. Theres also a wonderful twist at the end, as well as a parting thesis that The X-Files itself, especially in its revival seasons, could have taken a bit more to heart at times: Maybe some mysteries are never meant to be solved.Darin Morgans name became a regular fixture in later X-Files seasons, including penning a trio season three episodes that are now considered among the shows all-time best: Jose Chungs From Outer Space, War of the Cophrophages, and Clyde Bruckmans Final Repose. He also, certainly not coincidentally, penned and directed the two best episodes from The X-Files two revival seasons: season 10s Mulder and Scully Meet the Were-Monster, and season 11s The Lost Art of Forehead Sweat. You can stream The X-Files on Hulu. Want more io9 news? Check out when to expect the latest Marvel, Star Wars, and Star Trek releases, whats next for the DC Universe on film and TV, and everything you need to know about the future of Doctor Who.