Ninjas (AKA shinobi) were covert mercenaries in feudal Japan who were trained in the arts of espionage, sabotage and guerrilla warfare. In the 1980s and early '90s they became a popular subject matter in Western entertainment, with countless masked assassins popping up in movies, TV shows and comics.
For some reason, this freaked the hell out of the UK government.
British MPs have a habit of overacting to fictional media. In the 1980s, they banned so-called "video nasties" from sale. If a video store displayed uncut copies of Dawn of the Dead, The Texas Chain-Saw Massacre or The Evil Dead - all critically acclaimed movies, incidentally - the owner could find themselves tossed in jail.
Then there was the whole Mary Whitehouse movement, which frankly beggars belief. (Basically, some old ninny didn't like smut on TV and almost succeeded in having the BBC censored with the aid of high-profile politicians who were sympathetic to her cause.)
But by far the weirdest instance of government-fueled moral panic was the crackdown on ninjas. To this day, certain ninja-related paraphernalia remain illegal in the UK - not just to sell or own, but to even see.
We can understand the reasoning behind some of these bans. For example, nunchaku, shuriken and katana are controlled weapons in the UK for good reason - these things can kill people.
However, the widespread censoring of ninja-related entertainment is a lot harder to justify.
Until the late 1990s, it was essentially illegal to depict nunchaku (that is, two sticks connected with a chain or rope) in any form of entertainment - even when aimed at adults.
The government-run British Board of Film Classification (BBFC) would only grant a classification once the offending weapon had been removed. Consequently, thousands of British kung-fu fans never got to see Bruce Lee's iconic nunchucku scene in Enter The Dragon.
This is also the reason why the PAL versions of '90s video games always substitute nunchucku for weird bendy sticks. Namco's Soul Blade is perhaps the most memorable example of this, with the character of Li Long trading in his arsenal of nunchaku for a highly unconvincing three-section staff.
Similarly, the film adaptation of Teenage Mutant Ninja Turtles was forced to censor scenes of Michelangelo using his signature 'nunchucks' for the UK release. (On the animated TV show, he was given a grappling hook instead.)
You can see a full breakdown of all the cuts here.
This blanket ban was also imposed on the movie's sequel; Secret Of The Ooze. Hilariously, the ordered cuts even extended to a scene where Michelangelo uses a sausage link as a makeshift nunchucku. (Apparently, even cured meats are prohibited weapons when used by a ninja.)
But this wasn't the worst ignominy suffered by Teenage Mutant Ninja Turtles at the hands on the UK government. Not by a long chalk.
Throughout the 1990s, the brand name was forcibly changed to Teenage Mutant Hero Turtles. No, really:
The British Broadcasting Corporation considered ninjas to be far too violent for a children's TV show. Consequently, everything related to the franchise (including comic books, video games, clothing and toys) was renamed Teenage Mutant Hero Turtles specifically for the UK market. It really was as simple and as stupid as that.
Nowadays, the UK's cold war on shinobi has slowly begun to thaw. You can finally call turtles 'ninjas' and watch Enter The Dragon uncut. But you still can't buy a pair of sticks connected to a string. That's ninja gear.
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