Since its inception, anime and manga have been intertwined. See a good manga? Chances were it would get an anime adaptation if popular enough. As time went on, Japan started adapting light novels into anime. Video games. Visual novels. One certainty was that your favorite anime had some source material out there you could enjoy after the fact.
But there are some oddities. Some anime not only isn't based on a manga or light novel, but some don't even have source material. At all. Some of these original shows are trash. Others are brilliant works of entertainment. For the sake of argument, let's look at some of the cream of the crop. The amazing anime that with no source material -- some you might've heard of.
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10. Code Geass
The Empire of Britannia has conquered Japan, stripping it of a name and identity. Lelouch, an exiled prince, vows vengeance against Britannia after he participated in the nation's downfall. After an encounter with a witch named C.C., Lelouch gains the power of Geass, which allows him to break the will of any and all around him to obey -- or die -- at his command.
Code Geass is often touted as one of the best anime of the '00s. For good reason, too. It's politically driven, emotionally powerful, and epic in scale. Plus, thanks to CLAMP's character designs, it looks beautiful, too.
Though the manga-writing team CLAMP did work on the series, Code Geass doesn't use any of CLAMP's manga as source material. Several manga and light novels were inspired by the anime, but the anime itself is without source material.
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Is it even possible to explain the plot of FLCL without sounding completely insane? So Naoto is this kid who lives in a town where "nothing really happens" (lies), who runs into a crazy woman named Haruharu Haruko who rides a vespa, who then hits him over the head with a guitar, which somehow opens his forehead up as an interdimensional portal where a robot pirate lord can spring out to fight aliens and --
See what I mean?
Many regard FLCL as one of the most bewildering anime ever conceived by man. This is a Studio Gainax production (get used to seeing this name, as the majority of their best-known anime are without source material). With its incredible soundtrack, bizarre animation style, and drug-rattled plot, it's hard to even explain the anime's appeal beyond it being completely insane.
Haruka Nanase is a former swimming champion who runs into his old rival Rin. After reigniting their rivalry, their friend group starts a swimming club where they compete in swimming competitions. That's it. That's the series.
Free! started off as a series banking on the success of its attractive male leads. It drew in a crowd with its relaxing tone and quasi-competitive sports arcs. It became one of the most popular sports anime ever, drawing in international appeal all around the world (another anime may have gained broader international appeal, but we'll get to that later).
This one only just barely counts. It is based on a light novel by Koji Oji, but the light novel was published following the start of the anime by Kyoto Animation, the studio who produced the anime, and acts essentially as a prequel to the anime. The multi-media production of Free! and the anime's success predates the release of the light novel, which, in many ways, makes the light novel feel more like a proposal to the series than it being a legitimate source material.
7. Puella Magi Madoka Magica
Madoka, a teenage girl, has always been a bit of a dreamer. However, when she encounters an enigmatic entity named Kyubey, she is offered the chance to become a magical girl -- a hero who can fight evil witches and save the world -- AND gets offered one wish of her choosing. Sounds like a win-win situation, right? Well...if that's the case, then why does this enigmatic magical girl named Homura keep trying to prevent Madoka from making her wish?
Puella Magi Madoka Magica -- or just Madoka for short -- is often regarded as one of the high points of the magical girl anime genre. It may be easy to forget, despite all the manga spin-offs and other material, that the original Madoka anime had no source material. The series didn't have a manga or light novel it used as inspiration.
Or, at least, not really a source material in the traditional sense of the word.
Gen Urobuchi, the director of the series, drew heavily from Goethe's Faust when making the series. However, this does not make it the anime adaptation of Faust the same way that Gankutsuou is an anime adaptation of The Count of Monte Cristo. It is an original tale that draws from the old story for inspiration, not as source material.
6. Paranoia Agent
How does one explain Paranoia Agent? It is a strange hodgepodge of ideas legendary anime director Satoshi Kon had while working on prior films, such as Perfect Blue and Millennium Actress, that he couldn't fit into anything else. The result is this anthology series surrounding the actions of a boy wielding a baseball bat on skates and the bizarre horror that surrounds him.
This anime is barely based on an idea. It is based on the mad daydreams of one of the true geniuses of the anime medium. Satoshi Kon left this world too early, but the stories he left are all unique in their vision.
5. Yuri On Ice
Yuri Katsuki, following a devastating loss in an international ice skating tournament, goes from Japan's champion figure skater to a depressed stress-eating mess. However, when his source of inspiration and celebrity crush Victor Nikiforov flies all the way to Yuri's home in Japan to offer to coach him, Yuri begins to train for what may be his last chance to make history.
Yuri on Ice is arguably the most popular and critically beloved sports anime in recent memory. It features a diverse (albeit mostly male) cast of characters, a compelling cast of characters, and one of the most popular romantic couples in the 2010s era of anime.
It is also a completely original anime without source material. After completing the criminally underrated anime The Woman Named Fujiko Mine, anime director Sayo Yamamoto began work on this ice skating anime, drawing heavily from her love of figure skaters.
Yuri on Ice is also unique among this list because since, as of this writing, there are no manga or light novel spin-offs at all. There is a prequel film announced and the promise of a follow-up season. As it stands, though, Yuri on Ice remains a very short, very powerful anime.
4. Tengen Toppa Gurren Lagann
Simon is a digger living in an underground community with his "bro," Kamina. One day, they uncover a robot hidden under the soil. That same day, Beast Men from the surface come crashing down. That same day, Simon sets out on an adventure that will take him beyond the impossible.
Studio Gainax is at it again with this brilliant series about surpassing the limits of all logic and beyond. The series has been adapted into various manga spin-off titles, but the original series Gurren Lagann is a completely original story. Its incredible animation, vibrant action, and brilliant tragedy led to it becoming a staple of the anime community for years, despite the fact that the anime has no source material or built-in fanbase to draw attention to itself.
Yet it has become one of the most widely loved mecha anime of all time.
3. Mobile Suit Gundam
Amuro Ray, teenage boy living in the space colonies, finds himself falling into the seat of the colonies' greatest weapon against the Principalities of Zeon. Now, Amuro must pilot a Gundam, a giant robot powerful enough to turn the tide of war against Zeon. But, in doing so, Amuro must wade into the fires of war...and start a franchise still going strong decades later.
Mobile Suit Gundam is arguably one of the most important anime ever made. The original anime was the pure brainchild of one Yoshiyuki Tomino. The series has had numerous spin-offs, including multiple manga based on its run. However, the original series is completely and thoroughly original.
The same cannot be said for any of the follow-ups, as, essentially, later Gundams uses Gundam as its own source material, as seen by how often you see copies of series rival Char Aznable pop up in every follow-up series.
2. Cowboy Bebop
Spike Spiegel is a bounty hunter aboard the Bebop, a spaceship that travels through the solar system looking to earn a quick buck capturing the baddest of the bad. As he and his companions aimlessly travel through the solar system trying to survive, they encounter a cast of wild characters, all while the lives they left behind them find new ways to catch up to them.
The last two anime on this list are often regarded as among the greatest anime ever made. Anime buffs often regard them as masterpieces of the medium. But among American fans, there are few anime series better than Cowboy Bebop.
To the surprise of many, Cowboy Bebop doesn't have source material. There is a manga, but that is based on the series, and, presumably, takes place during the series. The original anime is primarily a collection of references to creator Shinichiro Watanabe's favorite pieces of entertainment. It is a pastiche of Western Culture. It is also a purely audi0-visual experience, designed with television audiences in mind.
As such, it makes sense that this anime is without source material.
1. Neon Genesis Evangelion
Fourteen-year-old Shinji Ikari is forced to get in the damn robot
Some regard Neon Genesis Evangelion to be Studio Gainax's crowning achievement. Others call it the greatest anime of all time. It's certainly the most controversial. Many have seen the Neon Genesis Evangelion manga (or its fan-ficy spin-offs) in bookstores all around the world, but before you start typing in your angry comments, just consider this: Evangelion's manga started at the same time as the anime, ended almost twenty years later, and was made by the anime's character designer, Yoshiyuki Sadamoto.
Indeed, the manga exists as Sadamoto's alternate interpretation of how Evangelion should have been. Essentially, it's fanfiction created while the anime was still deep in production, and continued years after it ended. But the anime has no source material. It's all a product of creator Hideaki Anno's disturbed imagination. It's incredibly telling that, years after the fact, a detailed description of the series's original plan came to light. It turned out that Anno didn't even use that initial outline as source material, since he basically tossed out all the old plans halfway through production. And you can tell EXACTLY where he tossed out the plans because that's the point the series delves into existential philosophy.
Evangelion is the sort of insanity you cannot plan. This anime is without source material. It is simply the sort of wild brilliance you can only get once you've gone too deep to pull out.