10 Most Unhinged Anime Mad Scientists

Anime has a penchant for over-the-top characters who bring to the extremes whatever they do, and mad scientists are the perfect expression of this. Over the years, anime (and manga) have shown some of the most unhinged mad scientists in fiction, as protagonists, supporting characters, and more often villains.

The figure of the mad scientist — whether their field is surgery, biology, psychology, or sociology — has been a staple of fiction for centuries. From Frankenstein to Faust to Moreau, these characters defy all rules and push past the limits of what’s possible. No cost is too great if it means their research succeeds. They will sacrifice their careers, bodies, and children for the sake of scientific progress, and when they do, it inevitably means horrific things for everyone around them, if not the world at large. These are the most unhinged and ruthless mad scientists in anime.

Before the mad doctor, there was the mad alchemist, pushing the boundaries of transmutation as far as they go. Shou Tucker has zero concept of boundaries that shouldn’t be broken, as the Elric brothers discover when he fuses his daughter with his dog to create a sapient chimera in Fullmetal Alchemist's darkest moment. He’s already done the same to his late wife and is determined to perfect his technique with the closest subjects on hand: the ones that love and trust him most.

Though Shou rambles about scientific progress, his raging ego and narcissism betray themselves in his every word. He has no concept of other people as worth consideration: they’re only for his use. When he’s caught, he has zero remorse, only bitterness that nobody understands his genius.

9 Cioccolata - JoJo’s Bizarre Adventure

Surgery is a delicate discipline based on thousands of years of medical science. Cioccolata threw all of that in the garbage even before he became an assassin and torturer for Passione. As a doctor, he purposely misdiagnosed patients as needing surgery to get them on his operating table, where he would cut them open with a botched anesthetic so that they could be awake and conscious of the pain.

After being fired for “accidentally” killing a patient, Cioccolata went fully unhinged as a criminal and joined the criminal group Passione. He expertly slices up Sorbet and Gelato, fellow Passione members, on the Boss’ orders, making the kill as long and torturous as possible. Even when Green Day is doing the heavy lifting, Cioccolata still uses his medical knowledge in battle, going as far as cutting and sewing himself up as necessary.

8 Akihiro Kanou - Tokyo Ghoul

Dr. Kanou is part of one of the best episode one plot twists in anime and a major turn towards the end of Tokyo Ghoul's manga. At first, the audience believes that transplanting Rize Kaneshiro’s organs into the mauled Ken Kaneki is a last-ditch effort to save Kaneki from dying. But Kaneki’s unwilling transformation into a ghoul was very purposeful.

Traumatized by his mother’s fatal illness and bent on forcing humanity to evolve past such things, Kanou is a human who joined up with the all-ghoul Aogiri Tree. Kaneki may be his prized lab rat, whose success he fervently wants to replicate, but he is far from Kanou’s only victim. He brutally tortures Takizawa and abandons Kurona and Nashiro, who allowed him to experiment on them out of loyalty, when they don’t measure up.

7 Huey Laforet - Baccano!

Writer Ryohgo Narita has created many mad scientist characters, from Szilard Quates to Shinra Kishitani to even Izaya Orihara. However, none of them are quite like Baccano!'s Huey Laforet, whose centuries of life have been wholly dedicated to his sociological and alchemical experiments. Everywhere Huey looks, he doesn’t see other people, only raw materials.

Beautiful and charming, he is charismatic enough to have an entire cult convinced he will make them immortal and his two daughters jumping at his every command. Chane and Leeza are some of his favorite experimental subjects, from readily agreeing to Chane’s request that her father take away her voice so she could never reveal his secrets, to having Leeza possessed by a homunculus that he also created.

6 Nina Einstein - Code Geass

At first, Nina is a bright but shy engineer who adores Princess Euphemia, but when she is killed in a disaster that changes the anime forever, Nina is irreparably broken as well. A shell of her former self frothing with grief for Euphemia and hatred for non-Britannians, she throws herself into creating superweapons to take revenge, able to whip up devastating power from the simplest ingredients.

In the most horrifying way possible, Nina proves that she lives up to her surname for sheer scientific potential. The F.L.E.I.J.A. missile that she develops and Suzaku is forced to fire levels Tokyo and kills 35 million innocents. Though this wakes her up to how awful her research really was, it’s too late: while she’s struggling to make amends, Schneizel is already hooking up his floating fortress Damocles with multiple F.L.E.I.J.A. missiles.

5 Washuu Hakubi - Tenchi Muyo!

As beautiful alien women fill his house, Tenchi Masaki learns very quickly that the universe is far stranger than he thought. One of the strangest things in it is Washuu, who is a genius in several fields of science. For twenty thousand years, she has done exactly as she pleases, no matter the consequences, all for the sake of amusing herself.

Not even being exiled and imprisoned in a gem aboard an impenetrable ship is enough to faze her. Washuu creates devices that lay waste to time and space, galaxy-destroying weaponry, and genetically engineered creations such as her daughter Ryoko. In one continuity, she is even one of the goddesses who created the universe: she simply never stopped developing new things from there.

4 The Doctor - Hellsing Ultimate

Taking terrifying inspiration from real-life mad doctors, The Doctor from Hellsing is cold, cruel, and ecstatic about creating the perfect weapons of war. With his surgical techniques, he creates Millennium’s vampire supersoldiers. He's also the reason The Major has his cyborg body, and he himself has somehow managed to maintain his youth for decades.

To fund his research, The Doctor will ally with anyone, even the Nazis of Millennium. His lab coat is perpetually covered in blood, the mark of every atrocity he’s committed, for which he has no remorse. The lives of his minions are as meaningless to him as anyone else’s: if they fail, he uses the microchips he implants in their brains to blow them up with the press of a button.

3 Orochimaru - Naruto

Orochimaru’s name is hated and feared throughout the Leaf Village for good reason. Craving immortality, Orochimaru conducted horrific experiments on his fellow villagers. When he was caught and exiled, he only expanded his subject pool, using young shinobi he manipulated into following him and smaller villages he subjugated. His research sinks to the very darkest depths of what Forbidden Jutsu are capable of, and at a terrible cost.

Orochimaru may have one of the highest body counts of any mad scientist in anime. In just one of his experiments with the First Hokage’s cells, sixty kidnapped children die under his knife. Controversially, Orochimaru is redeemed by the end of Naruto, and by the time Boruto takes place he is "simply" a weird man obsessed with science and a valued ally of Konoha.

2 Mayuri Kurotsuchi - Bleach

The Shinigami of Soul Society are lucky that Mayuri decides to stay on their side. From enemies to allies to his own severely battered daughter, he will happily subject anyone and everyone to painful experiments. Like Shou Tucker, he is baffled at the idea that anyone could take issue with what he does: he’s a genius, after all, so he can’t possibly be wrong.

Mayuri belongs to that subset of mad scientist who is more than happy to experiment on himself as well. In the pursuit of new discoveries, he has cut off his own body parts, rearranged his own organs, and given himself and his Bankai enhancements. He ultimately proves his superiority as Bleach’s alpha mad scientist by soundly thrashing rival mad scientist Szayelaporro Granz.

1 Franken Stein - Soul Eater

Ever since he was a kid secretly cutting open his weapon partner in his sleep, Stein made no secret of the things he loves most: dissection, dissection, and more dissection. In a world where Madness is a physical, powerful corruption of the soul, those susceptible to it like Stein are in true danger of giving in and becoming irrevocably transformed.

Soul Eater being the kind of series it is, Stein is firmly a good guy, more complex than the average mad scientist. Compared to the much more unstable mad scientist Medusa, Stein is at his core a good man, intensely protective of his students and constantly fighting to uphold his own morals, no matter how difficult it is for him. Where Medusa tortures her child Crona as an experiment, ultimately dying because of it in both anime and manga, Stein is (hopefully) only joking about making his and Marie’s baby a guinea pig.

Anime has also many "good professor" type characters who show us the miracles science can perform and often act as mentors for the protagonists. The characters on this list, instead, are the ones who remind us of the horrors that can occur if science is taken too far. Without care and compassion for anyone else, the experiments of these anime mad scientists bring only death and destruction.