Fox

In the 26th edition of “Treehouse of Horror,” The Simpsons’s Halloween special series, the villainous Sideshow Bob finally achieved his dream of murdering Bart Simpson, using a wacky reanimation machine to do it over and over again. He whacked him with a hammer, fed him to a lion, and pulled his guts out and wore them like a backpack. To hear it described, it doesn’t sound funny—and it wasn’t, but not for the reasons you’d think. In its glory days, “Treehouse of Horror” was television’s best mix of non-sequitur jokes and genuinely creepy short storytelling, even if it’s now more like a parody of its former brilliance.

Sideshow Bob’s triumph in “Treehouse of Horror XXVI,” which aired Sunday as part of The Simpsons’s 27th season, was a meta-joke about the character’s long-running string of appearances where he tries, and always fails, to take revenge on Bart for getting him arrested in the show’s first season. Each “Treehouse” episode has three short segments that take place outside of the show’s continuity, so anything can happen. This has turned into a blank slate for the show’s writers to indulge in postmodern jokes, but at its best, “Treehouse of Horror” transforms absurdity into art.

This year, a spoof of Godzilla turned into a fourth-wall breaking story about Hollywood remakes of foreign horror films, and the episode ended with aliens Kang and Kodos bemoaning their lack of story time and getting squeezed into an old-fashioned square aspect ratio as punishment. “Just because it looks like season four, doesn’t mean it is season four,” Kodos told the audience, a common refrain in The Simpsons’s later seasons.

Early “Treehouse of Horror” episodes were particularly avant-garde in their lack of emphasis on laughs. Though The Simpsons was a ratings smash, in its early years it was first and foremost a family sitcom that hadn’t yet developed the larger world of Springfield. After a successful debut season, the show tried out its first Halloween special in the second season, inspired by Halloween anthology comics of the 1950s, The Twilight Zone, and the thrill of telling a story “out of canon”—allowing the show to kill off characters or turn them into monsters without harming The Simpsons’s larger continuity. The first “Treehouse of Horror” has two straightforward horror-comedy segments (the family in a haunted house; the family getting abducted by Kang and Kodos), and ends with a surprisingly straightforward adaptation of Edgar Allan Poe’s “The Raven,” which has Bart in the titular role but otherwise mostly adheres to Poe’s text.

I’ve written about the audacity of “The Raven” before when discussing the legacy of Sam Simon, one of the show’s developers. He insisted on doing the segment despite the creator Matt Groening’s fears that it’d come off as too pretentious, and produced a lovely six-minute piece of animation that summarizes Poe’s famed tale for a family audience without sacrificing its dark core. Perhaps no other “Treehouse of Horror” segment would ever be as artful, but the episode’s success allowed the writers to continue pursuing nightmarish little tangents once a year, with enough jokes to keep the creepiness in check.

In “Nightmare Cafeteria” (from “Treehouse of Horror V”), Bart and Lisa find out their school is cooking misbehaving children and serving them as lunch; the episode is intense enough that it has them wake up at the end of it, dismissing it all as a horrible dream. As they wake, Marge assures the kids there’s nothing to be afraid of, “Except for that fog that turns people inside out.” Said fog seeps through their windows, and within minutes, an inside-out Simpsons family is doing a number from A Chorus Line to close out the episode—a brilliant example of how the show’s horror could turn on a dime from unsettling to funny and back again without inducing whiplash.

The following year’s “Treehouse of Horror VI” had a particularly bizarre dream-like quality that the show never equaled. In the first segment, giant advertising statues come to life and start rampaging through the streets of Springfield. The second, a spoof of A Nightmare on Elm Street, featured several scenes actually taking place in the dreams of Bart and Lisa, and embraced their unsettling lack of logic. The last was the then-revolutionary “Homer Cubed,” fully rendered in 3-D animation, which saw Homer venture into a peculiar CGI world and then the real world. Jokes became fewer and farther between, and each segment always managed to cram a traditional three-act story into a six-minute piece, retaining an old-fashioned campfire story vibe.

The mix of strict time limits and wide creative freedom in “Treehouse of Horror” led to stories that could be immeasurably wacky but satisfying at the same time. But in later years, the decline of “Treehouse” mirrored the decline of the show in general. Celebrity cameos became commonplace, and rather than spoofing classic horror movies or old Twilight Zone episodes, the show parodied recent blockbusters like Avatar and Harry Potter, even though they had tenuous connections to the horror genre.

In many ways, the appearance of Sideshow Bob on Sunday marked both a low point and a fitting salute for a show that seems to only survive on Fox’s airwaves because of profit-margin calculations. The Simpsons has run for so long that it now seems able to spoof itself, giving a well-worn character a chance to do something new. There was nothing particularly scary or memorable about watching Bob hack away at Bart over and over again, but the audacity served as a reminder of the creative freedom The Simpsons pioneered for years and years. Sideshow Bob may not be able to make killing Bart interesting anymore, but his recurring attempts pay homage to one of the real highlights of Simpsons history.

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