Few characters have shaped an artform in the same way as Jim Henson's Muppets. Ask any random person their thoughts about puppetry and inevitably they'll have something to say about Henson's creations. Sesame Street has been educating children worldwide for 48 years and counting, while the cast of The Muppet Show proved puppets could be just as (if not more) entertaining for adults as for kids. The Muppets' reputation as positive-minded kid-friendly entertainment means people frequently overlook the darker side of their material.

The fifteen secrets on this list reveal the Muppets' often overlooked dark side. The entries contain a mix of darker content in the Muppet series and movies themselves as well as dark real life stories surrounding their creation. Personal tragedies and behind the scenes conflicts shaped the evolution of the Muppets as we know them today. As fixtures of the greater popular culture, the Muppets have also been unwillingly dragged into some more messed up news stories. It's really not easy being green! This list is only the tip of the iceberg for sad, bizzare and surprising Muppet trivia. If you're aware of any particularly outrageous Muppet facts that were overlooked, please let the world know in the comments.

15 THE MUPPET SHOW: SEX AND VIOLENCE

Muppets Sex and Violence

Jim Henson never wanted his Muppet characters to be just for kids. Even so, one of his initial pilots for the project that became The Muppet Show is kind of shocking in its decidedly adult-oriented focus. The title of this 1975 pilot? The Muppet Show: Sex and Violence!

Violence of the slapstick variety has always been associated with the Muppets. Jim once remarked that there's only two endings for Muppet sketches: "Either someone gets eaten or something blows up." Sexual content, not so much. This pilot, focusing on a "Seven Deadly Sins Pageant," plays as if the Muppets went a more Monty Python route. It's rough around the edges, with a weaker host in the role Kermit would later fill, but an interesting "what could have been."

14 MISS PIGGY'S TROUBLED FAMILY

Muppets Miss Piggy Mother

In this age of prequels and spin-offs, it doesn't appear that anyone is particularly clamoring for a Miss Piggy origin story movie. If such a project were to exist, however, it sounds like it would be pretty emotionally intense. What little is known about her family comes from press interviews performer Frank Oz gave in 1979 to promote The Muppet Movie. It's not a happy story.

Oz told the New York Times, "her father died when she was young, and her mother wasn't that nice to her." He told People Magazine, "her mother had so many piglets she never found time to develop her mind. ‘I’ll die before I live like that!’ Miss Piggy screamed, and ran away to the city." In a Larry King Live interview on December 23, 1993, Miss Piggy confirmed she's not on speaking terms with her mom.

13 SESAME STREET'S BANNED EPISODE

Sesame Street Wicked Witch

If by chance you have a recording of Sesame Street episode 0847, hold onto it. You're in possession of something extremely valuable and rare. This episode featured guest star Margaret Hamilton reprising her role as The Wicked Witch of the West from The Wizard of Oz. It aired once on February 10, 1976 and never again.

Why was this episode banned? The Wicked Witch was just too scary for the Sesame Street audience. The Wizard of Oz is already potent childhood nightmare fuel, so including its villain on a show for the preschool crowd was just too intense. Not all of the parental complaints about the episode focused on terrified tots, however. One angry letter came from a self-professed Wiccan angry about the perpetuation of stereotypes about witches!

12 THE HENSONS WANTED STEVE WHITMIRE FIRED

steve-whitmire-kermit

In July 2017, Disney announced that Steve Whitmere, who played Kermit since 1990, was no longer working with The Muppets. Matt Vogel was announced as the new Kermit. The news came as a surprise in the press, but if you talked to members of the Henson family, this firing was a long time coming. They all really hated working with him!

Brian Henson (Jim Henson's son) says problems working with Whitmere go back to the '90s. Without going into specific details, he said Whitmere made "outrageous demands and often played brinkmanship." Cheryl Henson (Jim's daughter) called Whitmere "self-serving" and hated the way he changed Kermit's characterization to something more cynical. Muppets Studio's official statement condemned Whitmere "repeated unacceptable business conduct over a period of many years."

11 PARODIES KIDS BETTER NOT GET

Sesame Street Game of Thrones

Sesame Street earned its reputation as the best preschool show in large part thanks to the various parody segments that offer entertainment for parents. From the old "Monsterpiece Theater" bits to their popular viral videos on YouTube, the Sesame Street Muppets have a history of mixing jokes for adults with lessons for kids. Sometimes, however, you really better hope the kids aren't getting the jokes.

Pop song and superhero parodies are one thing, but capturing even a fraction of the eeriness of Twin Peaks in "Twin Beaks"? Playing "Game of Chairs" with Muppet versions of the Game of Thrones cast? Replacing True Blood's sexy vampires with grouches in "True Mud"? "Law and Order: Special Letters Unit"? Make sure the kids don't Google those for a while!

10 AN HIV-POSITIVE MUPPET IN SOUTH AFRICA

Sesame Street Kami

Sesame Street is no stranger to dealing with the sad and painful aspects of children's lives. In the United States, it has programs about what happens when a parent dies, serves in the military or goes to jail. Sesame Street's many international spin-offs also adapt themselves to cultural concerns. With that, the South African and Nigerian versions of Sesame Street introduced the HIV-positive Muppet Kami in 2002.

Kami's an orphan who contracted HIV in a blood transfusion and whose mother died of AIDS. It's an extremely dark story, but one all too relevant to many kids in African countries. Media reports gave the false impression this character was to be used in the American version of the show, which caused a panic among Republican congressmen threatening to cut PBS funding if the character was used to teach "acceptance of homosexuals" (as if Ernie and Bert didn't have that beat covered...).

9 ALICE COOPER TRIED TO STEAL THEIR SOULS

Alice-Cooper-Muppets

Of all the celebrity guests on The Muppet Show, Alice Cooper's appearance might have been the weirdest and, for younger viewers at least, the creepiest. It wasn't the only time the show went for a horror-themed episode. Vincent Price had already guest starred. By 1978, however, Vincent Price had been around long enough that parents appreciated him while Alice Cooper's shock rock was still controversial.

The Alice Cooper episode, the seventh of the third season, plays into his demonic stage persona. In the episode, he's a literal agent of the Devil, offering the Muppets "fabulous riches and worldwide fame"... in exchange for their souls! Miss Piggy and Gonzo were conflicted but ultimately decided not to take the Faustian bargain. Even the sketches without the guest star took a creepier vibe than usual.

8 QUENTIN TARANTINO THREATENED KERMIT WITH A KATANA

Muppets Quentin Tarantino

The 2000s were a dry spell for the Muppets. There were no theatrical Muppet movies between 1999's Muppets from Space and 2011's The Muppets, no new TV shows in America between Muppets Tonight ending in 1998 and The Muppets in 2015. The franchise's future was uncertain. However, there were new TV specials. One of them involved Quentin Tarantino threatening Kermit with a Katana.

The Muppets' Wizard of Oz in 2005 wasn't one of the Muppets' classics, only getting 38% on Rotten Tomatoes and being mostly forgotten today. One aspect of the special which is memorable for how weird it is, however, is a scene in which Quentin Tarantino goes crazy pitching a violent action movie version of the special. Somehow he also applies his foot fetish to Miss Piggy.

7 HENSON ALTERNATIVE'S ADULTS-ONLY PROJECTS

The rights to various Jim Henson properties are split up all over the place. CTW has the Sesame Street Muppets, while Disney owns the rest of the major Muppets. So what does The Jim Henson Company still have the rights to? They own Fraggle Rock, the Storyteller segments from The Jim Henson Hour and movies like Labyrinth and The Dark Crystal, but they also create new content. Sometimes this new content is for kids. Other times, it is absolutely NOT.

Look at anything under the Henson Alternative label and you'll find Muppet-style work unlike anything the mainline Muppets could get away with. In a sense competing with the Muppet parody Avenue Q, Henson Alternative produced its own dirty live puppet show Puppet Up. The R-rated puppet noir The Happytime Murders is set to release in theaters on August 17, 2018.

6 INNER TUBE REJECTED AS DARK AND PESSIMISTIC

Inner Tube Muppets

"Dark, victimized and pessimistic" are not words you'd usually use to describe a Muppet production, but that's how producer Larry Mirkin described Jim Henson's 1987 TV pilot "Inner Tube." The concept, involving characters travelling between various dreadful TV channels, was one that excited its creator for technological possibilities, but the pilot was ugly, unusually cynical and not all that funny.

The basic concept was reworked into another pilot, "Lead-Free TV," which still suffered from writing problems. The premise ultimately became the "MuppeTelevision" segments of The Jim Henson Hour, one of Henson's final projects and a rare at the time flop for the Muppet characters. The Jim Henson Hour was a grab bag, its "Storyteller" segments often far superior to its "MuppeTelevision" ones, and the more grotesque new Muppets like Vicki and Leon didn't catch on.

5 "MAH NA MAH NA" CAME FROM A SEXPLOITATION MOVIE

muppets-mah-na-mah-na

"Mah Na Mah Na" is one of the classic Muppet musical skits. It was regularly included on Sesame Street, performed on The Ed Sullivan Show and was even the opening scene of the first episode of The Muppet Show. It's fun, silly, energetic... and not a song originally written for the Muppets! Its origin? Something a lot less family-friendly.

Yes, "Mah Na Mah Na" originally came from the Italian sexploitation documentary Sweden: Heaven and Hell. The song plays over a scene of Swedish models hanging out together in a sauna wearing nothing but towels. The film also covers topics such as drugs, swingers, sex education and the porn industry. How'd the song become a Muppet staple? Sesame Street producer Joan Ganz Cooney heard it on the radio, devoid of the salacious context.

4 SADDER MOMENTS INSPIRED BY PAUL HENSON JR.'S DEATH

Jim and Paul Henson Jr

For all their absurdity, the Muppets always had an underlying sense of seriousness and melancholy. In the 30th anniversary special, Kermit flat out states his favorite parts of the Muppets are the ones which aren't focused on comedy. His nephew Robin responds saying, "Yeah, I always figured that was the writers' fault." This draws attention to how much of the more emotional moments came from Jim Henson, who had deeply personal reasons for such seriousness.

Jim's older brother, Paul Henson Jr., died in a motorcycle accident on April 15, 1956. Paul Jr. was 23 at the time of his passing. Jim was 19 and had just started his first TV show, Sam and Friends. The death impacted him deeply. Aware that death could come at any time, Jim put all of his energy into his creative work, coping with deep sadness through intense optimism.

3 BIG BIRD'S PERFORMANCE AT JIM HENSON'S FUNERAL

Big Bird Jim Henson Funeral

If you want to spend an afternoon just sobbing, watch the video of Big Bird singing "Bein' Green" at Jim Henson's funeral. Jim died of Toxic Shock Syndrome in 1990, far too young at the age of 53. He'd already laid out elaborate plans for his funeral, asking that nobody wear black, requesting specific songs and wanting it to be an uplifting celebration rather than a depressing occasion.

For all that spirit of positivity, all that planning couldn't stop the tears. No matter how positive your outlook, coping with a great person's unexpected death is a challenge. While singing "Bein' Green" at the funeral, Caroll Spinney hid his tears inside the Big Bird costume. If that final "Thank you, Kermit" doesn't get to you too, please check where you misplaced your soul.

2 THE RAINBOW CONNECTION HOSTAGE SITUATION

Rainbow Connection

What dark secrets could "The Rainbow Connection" possibly hold? Nothing in regards to the song's creation or its performance in The Muppet Movie, to be sure. Yet the world at large often seems as if it's out to ruin everything whimsical and innocent. That's how it must have felt to the manager of the Star FM radio station in Whanganui, New Zealand on March 22, 1996.

That day, a man claiming to carry a bomb broke into the station and took the manager hostage, threatening him to play "The Rainbow Connection" for 12 hours straight. The would-be terrorist was thankfully just bluffing about the bomb and police defused the situation. Why did this criminal cause this mess? According to Police Inspector Gary Smith, the hostage taker wanted to "tell people how he felt."

1 BIG BIRD ALMOST DIED IN THE CHALLENGER EXPLOSION

Challenger Explosion

At 83 years old, Caroll Spinney is still playing Big Bird and Oscar the Grouch. The 2015 documentary I Am Big Bird chronicles his storied career on Sesame Street. History could have gone very differently, though, had plans worked out for Spinney to fly aboard the Challenger space shuttle in his Big Bird costume in 1986.

The idea seemed like a good one at the time as a way to get kids excited about NASA and space exploration. It only didn't happen becase the Big Bird costume didn't fit in the shuttle. Schoolteacher Christa McAuliffe took Spinney's place on the January 28, 1986 voyage. The shuttle disintegrated 73 seconds into the mission, killing all seven astronauts aboard. Big Bird just narrowly escaped being the victim of a horrific tragedy.