The Science Hero was once a staple of adventure fiction, overcoming the Evil Sorcerer and awing the superstitious natives with the power of Science! But somewhere between the invention of the Gatling gun and the atomic bomb, fiction-creators deconstructed the archetype to create a new kind of villain: a villain who believes that the conventional scientific community are fools! Needlessly constrained by their petty "morals" and their self-limiting "logic"!

The Mad Scientist fulfills many needs for a story's creator, allowing the Scientist to fit into a wide range of stories. This is a mentally unsound type which allows the story's creator to cover a weak motive or Bond Villain Stupidity with a Hand Wave. This also helps the creator of the story explain why mad scientists kept all their incriminating records and yet don't have a duplicate monster or at least a blueprint lying around. Secondly, they're scientists, which in fiction means they can invent whatever strange device the plot requires. Thirdly, their insistence on weird experiments gives them artistic license to invent those devices. And lastly, a mad scientist is almost certain to violate the Scale of Scientific Sins: expect An Aesop (even if it's a preposterous one).

The Mad Scientist accumulates certain tropes effortlessly. Gadgeteer Genius and the Mad Scientist Laboratory (or "la-bore-a-tory") are almost obligatory, the scientist’s conversation is likely to include the phrases For Science! and They Called Me Mad!, and the Labcoat of Science and Medicine (classically, the Howie-style lab coat that buttons diagonally across the chest and has a Mandarin collar) can be expected. Most Mad Scientists are Large Hams: some employ Sesquipedalian Loquacity, while others specialize in the Evil Laugh.

Mad Scientists tend to be freely interdisciplinary — often omnidisciplinary — but some fields of science are especially well-represented.

• Mad Biologists trespass in God's domain, meddling with the bodies of the dead, the genetic makeup of their subjects and the very fabric of life to create horrific monsters, Super Soldiers and misguided attempts at immortality (often defined misguided because the plot says so, or otherwise because they work very, very badly). Inevitably, some or all of their creations will break free and either destroy them or go on a directionless rampage; sometimes, the Mad Biologist will set them free himself, either for revenge or just as a field test. In modern works, they often expand their research to fiddling with super-plagues.
• Mad Chemists are in many ways descended from sketchy alchemists of earlier eras. They often overlap with Mad Biologists to some degree, but tend to lean towards creating Super Serums and deadly toxins, usually either to sell to government programs or to hold a city hostage with by threatening to dump their creations into the water supply. Their laboratories are often richly adorned with Gratuitous Laboratory Flasks.
• Mad Engineers work with machinery first and foremost, creating Killer Robots, Death Rays, Doomsday Devices, armed vehicles of every sort, and occasionally even something practical. They often have an excellent working relationship with evil generals, warlords, and unscrupulous governments, making endless reams of weaponry for employers who don't generally care about petty things like "collateral damage", "moderation", or "war crimes".

Common Mad Scientist archetypes include:

• Absent-Minded Professor: A scientist who tends to get lost in thought and not pay much attention to their surroundings.
• Dr. Frankenstein: Victor Frankenstein himself, who created a patchwork creature in the Mary Shelley novel.
• Dr. Fakenstein: A mad scientist whose name is clearly a reference to Victor Frankenstein from Frankenstein.
• Evilutionary Biologist: The mad scientist's experiment involves improving the human race on his terms.
• Fate of the Frankensteins: A mad scientist who happens to be descended from Victor Frankenstein.
• Herr Doktor: Mad scientists tend to talk in thick German or Austrian accents.
• Maker of Monsters: Mad scientists who favor biology tend to specialize in creating large, aggressive and poorly controllable creatures.
• Mr. Exposition: A mad scientist is a very common form taken by a character who serves to explain plot details to the other characters.
• Mr. Fixit: If the mad scientist's main area of expertise is technology, expect them to be a whiz at repairing broken machinery.
• Omnidisciplinary Scientist: A scientist who is knowledgeable in every form of science that the plot requires.
• Professor Guinea Pig: Mad scientist often use themselves as test subjects.
• Robot Master: Mad scientists with a head for robotics often make heavy use of mechanical minions for their plots.
• Sole Surviving Scientist: In a post-apocalyptic setting, there is one scientist left alive who tries to undo the damages done to society, but isn't exactly right in the head.

Common Mad Scientist creations include:

• Applied Phlebotinum
• Bioweapon Beast
• Death Ray: A ray gun designed to instantly kill people.
• Doomsday Device: An invention created solely to cause astronomical death and destruction.
• Frankenstein's Monster: The mad scientist creates an artificial being that commonly takes the form of a hulking brute stitched together from dismembered corpses.
• Genetic Abomination
• Humongous Mecha: The mad scientist builds a giant robot.
• Killer Robot: Whoever would invent an automaton designed to kill people probably wouldn't be of sound mind.
• Kill Sat: A satellite armed with a powerful weapon.
• Monster of the Week: One-shot monsters are likely to be the result of a mad scientist's experiment.
• Time Machine: The scientist creates a machine that enables people to travel through time.
• Wave-Motion Gun

Other common tropes include:

• Above Good and Evil: Mad scientists will likely consider the importance of their research to outweigh such tawdry concepts as morals and ethics.
• Bald of Evil
• Cold-Blooded Torture: Some experiments these kinds of scientists do amount to torture.
• Creating Life: Near the top of the Scale of Scientific Sins, and one of the most common experiments prone to go horribly wrong.
• Einstein Hair: Nothing says "mad scientist" quite like having hair like Albert Einstein.
• Gone Horribly Wrong: Inevitably, a mad scientist's creations will backfire disastrously.
• Hollywood Hacking: Modern mad scientists have the capabilities of exploiting the technologies for their own causes among other reasons.
• The Igor: Mad scientists often have a hunchback or deformed dwarf as an assistant.
• The Madness Place: Mad scientists often lapse into hyper-productive fugue states when working.
• Mad Science Fair: Where all manner of Mad Scientist gather to showcase their various creations.
• Mad Scientist's Beautiful Daughter
• Morally Ambiguous Doctorate: Mad scientists are frequently villainous in nature.
• Playing with Syringes: Some of the viler mad scientists like to subject others to horrific experimentation.
• Science-Related Memetic Disorder: The trappings of science portrayed as a psychological compulsion.
• The Spark of Genius: Some scientists' madness is strong enough to warp reality.
• Techno Babble: Mad scientists' explanations of their works often lapse into incomprehensible jargon.
• They Called Me Mad!: It is very common for a mad scientist to go on a rant about how they were mocked for their ideas by their peers, especially when in the process of starting their experiment or unleashing their creation upon the world.
• Turned Against Their Masters: Inevitably, a mad scientist's creations will turn on their maker.

An increasingly common take on this trope is that Mad Science is a dangerous superpower or even a mental disorder, either hereditary in which case the afflicted may come from a long line of mad scientists, or transmissible through contagious ideas or experiences.

At times scientists will show signs of madness, but remain at least loosely allied with the heroes. In this case they may be somewhat demented smart guys, extremely Eccentric Mentors, Conspiracy Theorists, Professors, Playful Hackers, Psycho Sidekicks, Innocent Prodigies, Genius Ditzes or even Demolitions Experts. These 'tamed' mad scientists are emphatically not 'safer' than their diabolical brethren. If otherwise-(mostly) sane scientists start behaving crazily while they're in the throes of creativity, they're visiting The Madness Place.

If a work has several Mad Scientists, you can expect them to be distinguished by their particular field of interest. While the classic Mad Scientist relies on electronic or mechanical engineering (such as the Robot Master), there are others who become an Evilutionary Biologist, Psycho Psychologist, Sociopathic Soldier, Eco-Terrorist, Mad Bomber, Tech Bro or even The Cracker. And all of the above and more can likely be found at the local Mad Science Fair, eagerly showing off their latest crimes against nature.

If a scientist wants to concentrate on ordinary science but is being coerced into producing terrible things, they may be a Reluctant Mad Scientist or even a Kidnapped Scientist. A mad scientist with good intentions, publicly or not, can end up being a Well-Intentioned Extremist.

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