One day in 1985, while Jim Henson was wrapping up Labyrinth, a young Swedish filmmaker entered a boardroom to pitch Henson and his straight-laced British producer Duncan Kenworthy on a new movie. The filmmaker wanted Jim Henson Creature Shop to build fantastical-yet-lifelike animals for a movie called Animal Farm. As he continued to describe the project, it became clear that this was not an adaptation of George Orwell’s novel, but a pornographic film where the puppets would have, um, a starring role.

Henson, stone-faced, stroked his beard and listened, probing the filmmaker further on the prurient particularities of how the creatures would be used. After asking a clearly exasperated Kenworthy for his opinion on the project, Henson “exploded into his high-pitched giggle, unable to contain himself longer,” as Brian Jay Jones describes in his biography of the Muppet creator. Everyone broke character; the entire office was listening in behind the door. The pitch meeting was a prank to get a rise out of Kenworthy, a Cambridge graduate and a future BAFTA chairman.

Henson “clearly loved yanking people’s chains,” Jones told me, but the X-rated extent of this ruse would baffle any casual Henson fan. The prurient goof doesn’t align with the sensibility that drove his TV shows or movies, yet these kinds of backstage stories are prevalent. Though his public persona was that of a hip, latter-day Walt Disney, Jim Henson once responded to a viewer’s criticizing letter with a simple “What the fuck are you talking about?”

That was the Henson that Frank Oz, the iconic Muppet performer, knew. Henson worked in puppets and other media professionally for years before the creation of The Muppets and, later, Sesame Street. He had honed a creative ethos in those years, but that show solidified his national reputation as a children’s entertainer, since, of course, puppets are “for kids.” That assumption “really rankled my father,” said Jim’s son Brian Henson, director of the upcoming R-rated puppet comedy The Happytime Murders. “There is a naughty troublemaker that was at the center of my dad’s sense of humor and sensibility.”

Throughout his career, Jim Henson chafed against that reputation — for himself and for puppets in general — and fought it with sophisticated adult experiences, cheeky provocation and the abiding belief that puppetry could stand as a unique, challenging art form on its own.

The release and tagline (“No Sesame. All Street”) of this month’s The Happytime Murders, a vulgar spin on the Muppet movie tradition, irritated The Sesame Workshop to such a degree that the puppet shop filed a lawsuit. One glance at the fuzzy, round look of the movie’s cast summons Henson’s legacy, the signature design even causing one puppet in the movie to undergo plastic surgery to make him look more human. It’s easy to imagine the Sesame Street showrunners being wary of having their brand polluted as puppets perform kinky sex acts, get murdered by shotguns and generally act as crude as possible. Puppets seem innocent, and their perversion is both a source of comedy and a trigger of an alarm.

Subversive elements, however quiet or juvenile, were present in Henson’s work. His early influences — Edgar Bergen, Ernie Kovacs, the comic strip Pogo — had a level of satirical sophistication that was approachable to children, but his own work had a kind of anarchic joy to it that was previously absent from television and film. “Integrated chaos” was how a Washington Post reviewer described his first short spots on the local afternoon show.

Once he had launched 1955’s Sam and Friends, a popular daily program featuring an early turquoise and collarless Kermit the Frog, Henson said that “we had two endings: Either one creature ate the other, or both of them blew up … I’ve always been particular to things eating other things!” Sam and Friends featured novelty song lip-syncs and more experimental sketches that played with screen overlays and chopped-up sound bites, but the core of the show was driven by that goofy violent energy. It wasn’t exactly adult or as sophisticated as Henson’s influences — perhaps because the young Henson and his wife Jane had to spend so much time creating five days’ worth of sketches every week — but the show was unlike any other entertainment for children or adults. It was simple, but not simplistic. It was pure mania.

Henson honed his early, violent comedy into a sadistic science for a set of Wilkins Coffee advertisements. In a bewilderingly large number of popular commercials, a puppet, Wilkins, tries to make his grumpy, triangular counterpart, Wontkins, drink Wilkins Coffee. When Wontkins inevitably refuses, he gets run over by a truck, shot in the face, blown up, hit with a club, pushed from a great height, or made to suffer many other terrible fates. The setup and execution took eight seconds each time.

Not content with using Wilkins and Wontkins for one company’s campaign, Henson came up with scores more grisly scenarios for other coffee and food companies with the same characters. “It’s like watching a reel of Itchy and Scratchy,” said Jones. This isn’t especially groundbreaking or adult today, but in 1957, when the ad exec representing Wilkins approached Henson, she was specifically looking for “an edgy sensibility.”

Even after the initial Muppet success in Sam and Friends, the Wilkins commercials and, later, Rowlf the Dog’s star turns on The Jimmy Dean Show, Henson wasn’t convinced he would be staying in puppets; he thought of himself as an artist using puppets temporarily. Henson ventured into film and entertainment experiences to make his grand artistic statement unhampered by commercial constraints. The first of these was Time Piece, a short film that he said evoked “the story of the Everyman, frustrated by the typical tasks of a typical day” in fantastical, pre-MTV smash cuts.

Time Piece contained “non-sequiturs, women dancing in the nightclub, his head on a platter. That’s his more grown up sensibility,” as Jones puts it, “a great look into his creative MO.” Henson funded, conceived and directed the short himself, starring as the harried main character buffeted by the uncontrollable forces of modernity. His crew followed his instructions to bring about his opaque vision. “I didn’t know what the hell the movie was,” Frank Oz said to Jones. “I don’t think there was ever a project that came more [from Jim] specifically,” offered longtime collaborator Jerry Juhl, as recorded in the biography. There is an indie ebullience about Time Piece — Henson was finally free of the normative, crowd-pleasing necessities of television — but the style belies the substance: the frantic business of our lives that looks so meaningless in the face of ever-approaching death. The short would be nominated for an Oscar in 1965.

Take the visual overload of Time Piece, crank up the sexual energy and put it all in a futuristic nightclub, and you have Henson’s most ambitious and never-realized project of the 1960s: the Cyclia nightclub. Inspired by the psychedelic projections at a Jefferson Airplane concert, Henson wanted to commodify and amplify that experience. (Though he looked the part, Henson was a bit too old to be a true hippie and was as much a canny ad man as a Disney-esque dreamer.) As Jones describes it in his biography, “Jim envisioned that the walls, floor, and ceiling of his nightclub would be broken into faceted, crystal-like shapes onto which films would be projected — completely immersing dancers in a sea of images.”

The films, impressionistic segments of which were shot all around New York by Henson associates, centered on the chic, sublimated desires that would unleash at Cyclia. The whole experience presaged the overstimulating discos of the ’70s. Henson looked for club locations in New York and Los Angeles, but no viable space or budget quite met his grand designs.

After the enormous success of Sesame Street in 1969, Henson had some trouble getting back into the mode of creating his preferred mode of puppetry, one that focused on artistry rather than children’s entertainment. Henson performed with Nancy Sinatra in her Las Vegas show, responding to concerns over his choice with a curt “we have always worked in the realm of adults.” Ideas of a Muppet Broadway show emerged but could never get off the ground, as some of the avant-garde aspects, like being able to see the performers clearly behind the Muppets, turned off investors.

Eventually, Henson had his monkey’s-paw wish of being taken seriously as an adult entertainer granted: The Muppets appeared on the first season of Saturday Night Live in October 1975 — but with all-new, grotesque characters and no creative input from their creators. The “Land of Gortch” sketches went to the SNL staff member who drew the short straw, the head writer proclaiming, “I won’t write for felt.” The Not Ready for Prime Time Players also hated the idea of a sketch every week that none of them would be in. Oz put it as a question of mismatched sensibilities: “Our very explosive, more cartoony comedy didn’t jive with their kind of Second City, casual, laid-back comedy.” It wasn’t a matter of childish versus adult, but a matter of style. Brian Henson describes it as the most adult thing his father ever did, but it wasn’t truly his.

Amid this apparently fallow period, the second pilot for what would become The Muppet Show was being assembled, famously titled Sex and Violence. Though it clearly disturbed investors, Henson wouldn’t budge on the title, which rebuked his family-friendly image. Yet even with the show, “Jim felt he was already pulling his comedic punches,” as Jones describes it in his biography. Once it found funding from Associated Television in Britain, and a broadcasting arrangement in America with CBS, The Muppet Show became one of the most popular TV shows of the late ’70s.

The content of the show itself was, in Jones’ words, “not really dirty, but it was subversive stuff,” bringing up things like Animal brazenly lusting after Rita Moreno. Jones thinks that the achievement of The Muppet Show — something enjoyable for children but having that “wink wink, nudge nudge” sensibility for adults — might have satisfied Henson in terms of bringing sophisticated puppetry to the masses. Brian Henson made it clear that The Muppet Show was in some ways the apotheosis of his father’s showman sensibility. “There is a little of a subversive thing going on, an irreverence toward society, establishment, all of that.” Even Kermit was a bit naughty in how he quietly enjoyed introducing an act he knew would bomb.

Indeed, it may have been enough. Looking at Henson’s work in the last decade of his life, one can see how he began to focus on technological and narrative sophistication rather than adult thematic content or outright prurience. As Jones says, “Jim’s superpower was world-building.” Projects like The Dark Crystal, Labyrinth and TV’s The Storyteller began to occupy his mind, as well as Disney’s acquisition of The Muppets, which was stymied for 14 years after his unexpected death in 1990. You can see the depth of craft needed to execute the puppets’ larger movements down, to the minute articulation of their eyebrows. Even the sets were completely detailed in areas that the audience would never see. Fantastic immersion became Henson’s MO.

Of all things, Labyrinth retrospectively became Henson’s most adult project, at least in terms of continued appreciation. As Jones makes clear, “There are a lot of hands on that script,” citing Elaine May, George Lucas and Terry Jones. “If you want to look for something reflecting Jim, it’s harder to tell,” but collaborators attribute to Henson moments like the ballroom scene — where Jareth the Goblin King (David Bowie) seduces Sarah (Jennifer Connelly) in a dream sequence — and the M.C. Escher staircase scene.

Bowie’s charisma, especially as he is seen now rather than the poppy juggernaut that he was in the ’80s, is certainly part of the dark feel of the movie. “You have a young teenage child — she is a child — going with some adult feelings and trying to maneuver the dangers of that,” said Brian Henson. And Jareth is “basically trying to seduce a young teenager.” It has all the sublimated Freudianism of a Grimm fairy tale, all while the 13-hour clock ominously ticks away like its counterparts in Time Piece.

Though we never saw an explicitly (or explicit) adult production from Henson, Jones “could easily see Jim enjoying Puppet Up,” Brian Henson’s live, half-improv and very dirty puppet sketch show from which The Happytime Murders’ sensibility grew. Brian Henson said he “found that [his Puppet Up audiences] like it very blue, bluer than they want from people, quite honestly. They don’t get uncomfortable, and they kind of gleefully enjoy it.”

Rather than being appalled by the existence of dirty puppets, audiences love “when you remove that innocence,” said Brian Henson. That transgressive quality, combined with expert puppetry and the particular “game-ness” that Henson puppets naturally exude, made for enough of a hit live that Henson wanted to do “a darker piece” that had fleshed-out characters and flesh characters alongside the felt ones. After the script for The Happytime Murders lay dormant for years, Henson eventually picked it up and worked with the screenwriter to bring the project to fruition.

As it exists — Brian Henson said they had to cut some of the “deeper, darker moments” of the story to fast-pace the jokes — The Happytime Murders is far more mature than any other Henson product. And while“the center of this movie is not innocent” and “none of the characters are lovable,” as Henson put it, it’s clear that he wanted to do more than just push the envelope like hard-R, puppet movies such as Meet the Feebles or Team America: World Police. There’s a chaotic absurdity about the proceedings on the screen, one tinged with joy rather than cynicism. “The two dirtiest scenes,” as Brian broke it down, “one involves milking a cow and one involves silly string. [...] You make these very dirty jokes, but they’re funny because you make that ridiculously innocent choice right in the middle there.”

The movie doesn’t maliciously undermine of the art of puppetry. Instead, it harnesses a latent power in the Henson brand: a madcap “irreverence toward society.” But rather than a simple corrective to stuffiness and propriety, the irreverence in The Happytime Murders is an imp of the perverse, pointing out that bit of the “miscreant puppet” that lives in the viewer.

Jim Henson’s inner “naughty troublemaker” has a lot in common with that “miscreant puppet,” but it was always restrained by his intended audience and his sense of propriety. Then again, Jones offered an image of what Jim Henson might be doing if he were still around: “I think he would have loved Puppet Up. I think he would have loved Avenue Q. […] Especially now that he would be around 80, he would probably be having a blast.”