Everyone knows her. That one girl in your class, who won't ever shut the frick up and answers all of the teacher's questions before they've even been asked. Her voice constantly drones on as she tries to impress everyone, when really we all just want her to chill out and take a damn breather for once.
I swear, you're starting to make these topics up. 'Mary Sue'?
Or Marty Stu, depending on their gender. At first glance, most people aren't going to know where this sin is going... but for those English majors out there, I can practically hear their grumbles of egotistical approval already.
As you probably guessed, the term 'Mary Sue' was coined as a form of satire; a play on the overused archetypes that nearly every story protagonist gravitates towards. There are different levels and reasons for one to become a Mary Sue, but often it boils down to either shameless wish-fulfilment, or laziness on the author's part.
Uh huh, that's great and all... But you still haven't told us who Mary Sue is?
If you want a history lesson, Wikipedia's right there buddy. The short version is that she is a story-breaking character, who happens to be the central pillar to an entire plot. Everything in the book revolves around a Mary Sue type, from conversations to doors magically flying open just to let her through.
A better example of this, would be any protagonist or side character who is overwhelmingly attractive, suffers little-to-no hardships in the story at all and always leads the cast as 'the voice of reason'. Think of them as carrying a secret magic wand in their back pocket, which acts as a free pass for them to abruptly resolve any conflict with a Deus Ex Machina swish.
Deus Ex? Isn't that a video game? Why do you keep referencing terms that no one understands?!
How else am I supposed to flaunt my vocabulary to strangers on the internet? I need that sweet, tasty virtual credit!
Seriously though, Deus Ex Machina just refers to any dangerous situation where the heroes are left without hope, and a sudden unexpected power comes into play and saves the day. Why is this relevant? Because you'd better believe that your typical Mary Sue will abuse her unrealistic Deus Ex abilities like a button-masher in Street Fighter.
This kind of 'fascinating' character comes in many forms, so let's have a little run-down of how painfully awkward each genre's Sue/Stu can become, barring any chinks in their everlasting plot armour.
Romance: Absolutely stunning, straight-A high school girl attracts all of the dudes in her class upon entry, even some of the chicks without trying, but she wants the bad boy who pretends not to notice her good-girl ways... Except that he totally does, and then they live happily ever after until she dumps him for her taboo Phys Ed coach. Who is also madly in love with her, duh.
Thriller: Newbie private investigator with incredibly-chiselled jawline decides to clean up his home-town, starting with the latest in a series of grizzly murders. Every deduction he makes is on-point and accurate before the evidence has even appeared on-screen, and the mystery killer is caught without incidence. Because he's actually good at his job, this makes for a 'thrilling' Point A > Point B read.
Action: Two boxers, one ring. An underground match, only one will be able to walk out alive. Bets have been placed, the bell rings... The opponent starts to move, but then handsome Marty unhinges his mouth like a cobra and lets his ultra-mega-hyper-death rainbow beam of doom explode from the orifice, instantly melting his rival's face and reducing him to a pile of multicoloured goop. The crowd goes wild and he gets laid like 20 times that night, because why the hell not.
You didn't even try on that last one.
Exactly. No one wants to read a story where everything is automatically resolved after three seconds, with characters so overpowered they might as well be god-tier cheat codes. It makes for a boring journey, when you know that they can just pull a freaking bazooka out of nowhere and pulverise any enemies or logic that could be lurking in the vicinity.
It can simply be that the author isn't a stickler for realism, and thinks that because they're writing 'fiction', common sense doesn't have to apply. Let me tell you, even in the deepest of Fantasy niches, Mary Sues are never going to be as popular as the grounded, well-adjusted characters with discernible flaws.
As far as wish-fulfilment goes, some authors believe that the best characters are ones that have no weaknesses, like in real life... but those little nicks and scratches that the protagonist picks up as the plot moves forward, that's called development. Good luck trying to flesh out a character that you've decided is already 100% perfect in every way.
I won't discuss why wish-fulfilment and self-insertion is a terrible idea, as it should be obvious, and I'm particularly looking forward to tearing that wall down in a future sin. Instead, let's better understand this trope by listing off what many perceive to be 'Mary/Marty Sues' in more popular franchises.
Bella Swan, 'Twilight' (Are we surprised? She is literally the most unremarkable character, and yet every supernatural hunk wants a piece of that action)
Superman 'Silver Age Superman' (His eyes are freaking laser beams... and his only crux is an ultra-rare crystal fragment from outer space. Whenever he comes across a plot barricade like that, he just grows a brand new superpower and trolls on through)
The Doctor 'Doctor Who' (As much as I hate to admit it, he really does like to use made-up words to cement his invincibility. Whether it's reversing polarities or wibbily-wobbily timey-wimey, he's more of a Deus Ex Lord than a Time Lord)
Lara Croft 'Tomb Raider' (Extravagant mansion? Check. Butler who lives in your freezer? Check. Excessive athletic ability? Check. Big boobs? Double check. Everyone's favourite adventurer might be fun to play as, but from a character standpoint, it seems like some developer at Eidos was projecting a little too much)
Jeez dude, way to crap all over everyone's fandoms! Your inbox is gonna be on fire...
Don't get me wrong, I'm not saying that all Mary Sues are terrible characters. In fact, Mary Sues aren't 'characters' at all, it's merely a plot-advancing persona that most protagonists adopt. Even my main characters can be big ol' Sues, and that's something I've recently noticed and have been trying to rectify. Literally any character can slip into the author's favour and gain an inflated status, even for a single scene.
Is this the part where I ask how to avoid doing the sin thingy? *shuffles script pages*
Yup, thanks for the segue. In all honesty, you just have to practice catching them out in everyday life. When you're watching a TV series or any fictional media, try to really think about the characters as individuals. If you look at each on their own and discover that their only purpose is to ask dumb questions and make Mary look clever on-screen, chances are that her last name is Sue and they are all her soul-sucked victims.
These superlative ladies tend to be black holes that everything else in the story revolves around, people bending over backwards or flitting in and out of plot purgatory just to 'help them out' in a certain scene. They are unrealistically beloved by everyone, able to talk or even laser their way out of every situation with enough self-righteousness to make you vomit rainbows from your mouth-hole.
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Mary Sues are reflections, windows into what an author perceives to be a perfect individual. The reality we live in though, is that humans are consistently imperfect and this drive for completion is what motivates us to improve our daily lives.
There's a condition called Paradise Syndrome, a mental state that occurs when a person believes that they have achieved everything they could ever possibly want. They have no dreams, no ambitions, and therefore fall into a deep depression and eventually succumb to suicide. If Mary Sues existed in real life, the human race would be extinct in a matter of weeks.
Don't be a 'perfect' Mary Sue. Be you, or rather, be who you currently are instead of what you could be. Draw from your own difficult experiences, your own beautiful flaws and hardships, because that's how the most relatable characters are created. Why would you want to be someone else, when being who you are got you this far?
So, like, I just noticed this awesome formatting thing you did-
Next time, pal. Next time ;)
Oops, spoilers.