Every generation has had its iteration of the Teenage Mutant Ninja Turtles. Be it the grim and grisly Mirage comics, the world-changing original animated series, the 2003 anime influenced reboot, the 2012 digital update or Michael Bay’s current film franchise, the Heroes in a Half-Shell have been a persistent staple of pop culture for over 30 years, and they show no signs of slowing down. With the current animated series and comic book going strong, the Green Machine may not have touched the peaks of its original success, but it still doesn’t look like it’s going anywhere.

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As with any franchise that has existed for 30+ years, the TMNT have more than a few skeletons in their closet. Awkward interactions, forgotten storylines and truly mortifying live-action interpretations pepper the history of the Turtles, for better or worse. We’ve rooted around in the sewers to find some of the most egregious examples of these, and we’re dragging them up to the surface for all to see. Though nothing has happened yet or presumably could happen to truly ruin the legacy of the Ninja Turtles, these instances certainly tried.

15 THE SHREDDER’S KITCHEN ORIGINS

Despite dying in his first appearance, The Shredder has remained a prevalent force in the world of the Ninja Turtles. The central villain of the original 1987 animated series became a pop culture staple and has appeared in some form in nearly every Teenage Mutant Ninja Turtles production ever since. So fans might be surprised to learn that Shredder’s origins are from a much more innocuous place.

As discussed in Behind The Shells, a making-of documentary produced for the 1990 Teenage Mutant Ninja Turtles film, series co-creator Kevin Eastman reveals the character is the result of a kitchen implement gag. After washing some dishes, Eastman found himself holding an old box-style cheese grater, which he put on his forearm and commented to Peter Laird about how much fighting someone with similar weapons would hurt. The idea germinated into the creation of The Shredder as we know him today.

14 TEENAGE MUTANT NINJA TURTLES 4?

The original Teenage Mutant Ninja Turtles film was released in 1990 to surprising critical response and box office success, and successfully adapted the gritty tone of the comic books. Unfortunately, it also brought on a fair share of criticism, leading to the sequels steering away from violence and becoming more in line with the content of the wildly popular cartoons.

Though the original film franchise ended with the release of Teenage Mutant Ninja Turtles III, this wasn’t always intended to be the case. A fourth film was in the works which would return the franchise to its gritty roots, though it didn’t get very far into production. Concept art did leak, though, including a fifth turtle, Kirby, who had claws and a tattered cape, as well as April O’Neil with a sheer top and katana, as well as a returning Shredder with stylized armor and what appears to be Kabuki styled makeup.

13 APRIL O’NEIL’S KIRBY CONNECTION

As anyone who has taken the time to read the original Teenage Mutant Ninja Turtles run from Mirage knows, they get weird. There’s a lot of bizarre stuff, but chief among them may be the Kirby Crystal. Introduced when Donatello met Kirby King (an obvious reference to Jack Kirby), the Crystal would bring any drawing to life, but the pencil drawings would only last a brief period.

Sometime later, it was discovered that April O’Neil’s father had been in possession of the Kirby Crystal and drew a baby using a pen instead of a pencil that appeared to not disappear. The

revelation that she may actually be a magically-brought-to-life drawing led to April disappearing from the titles briefly. Upon her return, though, she only made oblique references to coming to terms with the revelation, and it was never brought up again.

12 THE SPACE COW HEAD

As was previously mentioned, the old Teenage Mutant Ninja Turtles comics got weird. It didn’t help when the line went to Archie Comics, which created Teenage Mutant Ninja Turtles Adventures, a series designed to play off the success of the cartoon. The show featured a number of characters from the show but also introduced its own original characters, and that’s where we got Cudley the Cowlick.

Cudley is a floating cow head that travels through space, and can carry people to faraway lands in his mouth. Cudley makes his first appearance in an early Teenage Mutant Ninja Turtles Adventures issue, carrying the Turtles away to a distant asteroid to participate in an outer space wrestling match. Cudley made a number of appearances afterward but hasn’t been seen in some time.

11 THE TURTLES AS MURDERERS

For most fans, the first exposure to the Turtles was the 1987 animated series. Adapting very little of the original stories, the cartoon was brightly colored and excellently animated, but very clearly aimed at young children. This made for more than a few awkward moments as those same kids grew up and discovered that the original Ninja Turtles were stone cold killers.

The original iteration of the characters were trained explicitly to take revenge on Shredder, and outright killed him in the first issue. Eastman and Laird have gone on record that they had created the characters as hitmen of sorts, owing to the nature of the very properties they were parodying. Though the animated series set the tone in the mainstream, the comics retained their darker tones for much of their run, until that line ended when IDW got the rights in 2011.

10 THE IMAGE COMICS RUN

The rights for Teenage Mutant Ninja Turtles comics changed hands a few times over the years but notably went to Image Comics in 1996. Image Comics had been riding high as a brand for some time, based on the strength of the art and the insanity of the stories. But the run the Ninja Turtles had at Image Comics really took the cake for just how insane the line could get.

The series radically changed the franchise, and not for the best. Donatello was critically wounded and turned into a cyborg, while Raphael was disfigured and found himself becoming The Shredder and leading a rejuvenated Foot. The team spent much of the 22-issue run fighting amongst themselves and chasing Splinter, who had mutated into a bat. The run was poorly received and was removed from the official timeline when Mirage reacquired the rights in 1999.

9 THE TURTLES ON OPRAH

The Turtles had a number of live action appearances, but by far the most surprising was the Coming Out Of Their Shells tour. Running in 1990 and endorsed by Pizza Hut, the tour is laughed at now by fans for cheap costume quality and the ludicrous idea of a Ninja Turtles musical, but it’s easy to forget it was popular enough to spawn a number of musical follow-ups.

Perhaps the less is said about Coming Out Of Their Shells, the better, but they almost certainly wish you could forget the Turtles appearing on Oprah Winfrey. The current production teams would probably rather you didn’t remember the Ninja Turtles admitting to trying to convince April to partake in an “interspecies relationship” on television. The rest of the interview has been all but forgotten, but that line has been popping up for years as the single most awkward moment in TMNT history.

8 THE SURROGATE SISTER

The Next Mutation

Airing on FOX in 1997, Ninja Turtles: The Next Mutation remains in a strange place in TMNT history. It’s unclear as to where the series fits in, with some sources considering it a follow-up to the movie franchise and some promotional material treating it as the sequel to the 1987 animated series, which had concluded in 1996. Airing for one season and a notable Power Rangers crossover, the series was quietly canceled after 26 episodes.

Regardless, the series is now known for only one thing: Venus, the team’s surrogate sister. The design has been discussed plenty in the now 20 years since it aired, with Peter Laird proclaiming she would never appear again. So far, that’s held up, with only a tongue-in-cheek, blink and you’ll miss it reference on the 2012 animated series and an oblique comic reference to a shapeshifting alien resembling a female turtle appearing since.

7 TEENAGERS FOREVER?

Teenage Mutant Ninja Turtles paints itself into a corner almost immediately by detailing the age of the characters in the title. And, in fact, this isn’t always an accurate identifier. For several instances of the titles run, the Turtles weren’t teenagers. For much of the original Mirage and Image line, the turtles aged in relative real time and, by the time of the Mirage timeline's conclusion in 2014, were in their 30s.

Since the acquisition of the rights by Nickelodeon and the comics being taken over by IDW, the age has been more consistent. The brothers are typically stated to be around 15 years old, and appear to age roughly half a year for every year of real time when necessary. In most cases, though, these ages are simply just not referenced, and the Turtles are left perpetually as Teenagers.

6 THE ANIME

In 1995, a Japan exclusive, two-episode OVA hit the markets. The art style was initially similar to the popular animated series, which was reaching its swan song as the Turtles acquired new mutations and the stories began to run long in the tooth. The Japanese creators weren’t worried about this, though, and crafted something entirely new.

By claiming the Mutastones, the Turtles were able to transform into Super Turtles, while Shredder transformed into Devil Shredder. The second episode was similar in tone, with the Turtles gaining armor and the ability to fuse into one powerful creature. The OVA episodes never received an actual American release, despite the continuing popularity of the Turtles. The episodes do not have an official release or translation to this day, making them only more conspicuous by their absence.

5 THE ORIGINAL "BAYLIENS" SCRIPT

Michael Bay’s 2014 Teenage Mutant Ninja Turtles reboot ultimately did okay, with the property being well-enough received and the filmmaking enough money to warrant a sequel. The film did gain some criticism for the numerous changes it made to the franchise, though, such as updated origins and designs, but it was almost much, much worse.

During a production upfront in 2011, Bay cited the Turtles in his iteration were not mutants, but aliens who were fighting against a military officer, Colonel Schraeder, who led an assault team known as The Foot. Shortly after, a script was leaked on the Internet that was never confirmed as legit, but Paramount quickly issuing takedown notices and refusing to comment lends it credibility. Bay’s film went into a production hiatus and was retooled into the updated franchise we eventually got.

4 ACROSS THE POND EDITING

Teenage Mutant Ninja Turtles wasn’t just an American institution, but a worldwide phenomenon. However, not every country received it as well. The show was notably censored in the UK, which had a long-running ban on anything related to ninjas. As a result, the show was retitled to Teenage Mutant Hero Turtles, and Michelangelo’s Nunchucks were removed.

The censorship had its effect on the franchise, with Michelangelo's Nunchucks being replaced by a grappling hook called the Turtle Line starting in Season 3. Further, Teenage Mutant Ninja Turtles II was written so that none of the Turtles used their weapons in response to criticism of the first film’s level of violence, though a scene where Mikey uses sausages as nunchucks was still edited out in the UK. By the time of the 2003 series, the ban was relaxed, and the Turtles were allowed to be Ninjas again.

3 THE PSA

You probably watched your share of PSA films if you grew up in the ‘80s or ‘90s, but somehow none has been as infamous as Cartoon All-Stars To The Rescue. Airing in 1990 on the three major networks, the short was an all-ages anti-drug PSA featuring a number of popular animated characters, including Winnie The Pooh, the Muppet Babies and Alvin and the Chipmunks.

Michelangelo appears briefly in the PSA, but one has to wonder if the team behind TMNT was particularly proud of this. After all, he’s the only character in the film to not appear on the cover art for the VHS release. Regardless, the film is largely only available as a bootleg these days, having never gotten a DVD release or even a widespread VHS release. Given the current edgier slant of the TMNT franchise, it’s likely the TMNT creative team would rather keep it that way.

2 SPLINTER’S DEATH

Mirage regained the rights to the Ninja Turtles after the Image run concluded in 1999, and soft rebooted the titles. The series ignored the years at Image, returning the Turtles to their original appearances and doing away with some of the weirder elements. However, it didn’t hesitate to change either, as issue #10 saw Splinter unceremoniously die alone of a heart attack.

The death stuck, with Splinter being dead for the remainder of the run... or so it would seem. Thanks to a long series of delays as Peter Laird worked on other projects, Teenage Mutant Ninja Turtles #32 released in 2014 and ended on the cliffhanger that the Splinter who had died was not the real Splinter. However, further issues were never released, as the rights were picked up by IDW, who again rebooted the line to match the style and tone of the new animated series.

1 THE CHRISTMAS SPECIAL

The Ninja Turtles have fought evil ninjas, maniacal super villains and come back from the brink of death, but they could not defeat their greatest challenge: obligatory gifts surrounding a holiday. In We Wish You A Turtle Christmas, the brothers realize that they have forgotten to get Splinter a present and dash to the surface to find him one.

Many live-action incarnations of the Turtles have been jeered, but none so soundly forgotten as We Wish You A Turtle Christmas. The special, only released on VHS in 1994, is almost universally panned for its awkward concept, sub-par songs and the poor quality of the Turtle costumes. While there is some entertainment value to be found in the other live-action Turtle musical jaunts, this one seems relegated to the dustbin of history, and it seems likely that that’s exactly how TMNT creators would like it.

Can you remember any Teenage Mutant Ninja Turtle fare that we should all collectively forget? Let us know in the comments!