American Horror Story: Murder House (2008) is the first installment of the American Horror Story franchise, and its cast of characters are some of the most tragic, twisted, dark and disturbed ever crammed on the small screen. The scariest thing about AHS: Murder House is there seems to be an infinite amount of ways people can both suffer and inflict pain on others, perpetuating a cycle of misery that guarantees peace for none.

RELATED: AHS:1984: 5 Reasons It's The Best Season (5 Why It's Not)

Eleven years after its premiere, the AHS: Murder House characters remain compelling figures, with some even resurfacing on American Horror Story: Apocalypse. Here's a ranking of Murder House's creepiest characters, and why their stories still keep audiences up at night.

Chad Warwick

To be fair, Chad (Zachary Quinto) isn't creepy most of the time. He's just a guy who wants to be loved who is prone to tantrums when things don't go his way.

It's when he decides to play daddy to Vivien's twins that Chad reveals a homicidal streak that either originates in the house or is nurtured by residing in it. Chad plans on being a great father ... forever thanks to filicide. Killing toddlers is dark, but when it comes to American Horror Story, nothing and nobody is off-limits.

R. Franklin

Serial killer Franklin (Jamie Harris) sets his sight on nursing students who live in the house in the '60s. There's never any doubt Franklin is going to go through with whatever he's got planned, it's just a question of how gruesome it will be.

He's not tied to the house in any way, he's just a random guy who takes advantage of a nice girl. Franklin appears bored or puzzled by one girl's tearful praying. Given Franklin's apparent disdain for any deity, the young woman's faith agitates him even more. Almost everything about Franklin is a question mark -- a harsh reminder about the randomness of violence

Thaddeus Montgomery

Thaddeus is a scientific experiment gone wrong. Nobody knows what Dr. Charles Montgomery (Matt Ross) does to the remains of his baby boy, but the result is a hissing, hideous hybrid.

RELATED: American Horror Story: 10 Unanswered Questions We Still Have About Cult

Thaddeus is an amalgam of every monster that occupies children's minds complete with rows of sharp teeth, claws and a face not even his mother can love. Thaddeus is the reason most kids won't venture into their basements. One encounter leads to a lifetime of nightmares.

Fiona

Fiona (Azura Skye) is the unspoken leader of the threesome who hopes to recreate R. Franklin's murders in 1968. Scarier than her black mask is her methodical determination to kill Violet (Taissa Farmiga) and Vivien (Connie Britton) exactly as Franklin did the two nurses.

With the overload of violence on AHS: Murder House, serial killers seem almost mundane, but it's the In Cold Blood/Helter Skelter vibe that is terrifying, even though the home invaders fail at their task. Is it the fact that Fiona is slight with a voice so high it borders on cartoonish that makes her so insidious? Or is it because serial killers are rarely women: a fact Murphy joyfully overlooks?

Dr. Charles Montgomery

Matt Ross in American Horror Story Murder House

Although there was a time when Montgomery had a successful career and a grasp on reality, he loses it all thanks to drug addiction. He fails to be interesting when he's piecing together animal parts and being nagged by his wife.

The good doctor's body count is far less than some of the other residents, taking one heart for what he considers a good cause. But his fondness for dismembering people and doing weird stuff with their parts is grotesque.

Michael Langdon

The ominous threat Vivien's baby poses begins in the womb. Even Vivien senses something wicked is coming when she dreams of the baby practically scraping at her insides. The plot is either an unapologetic ripoff of or an homage to Rosemary's Baby but updated by Murphy with his signature horror style.

RELATED: American Horror Story: 10 Unanswered Questions We Still Have About Freak Show

But while Roman Polanski's story of Satan's spawn ends before it begins, Murphy makes sure to leave viewers rattled when the final moments of the series reveal a blonde child who looks like an angel covered in the blood of his babysitter.

Hayden McClaine

AHS Murder House Hayden

Hayden (Kate Mara) may be a stage 5 clinger when she's alive, but she takes it to a whole other level once she dies. Sadly, death releases her from any repercussions or guilt over her actions which turns Hayden from a woman scorned into someone far more nefarious.

An ongoing theme on AHS: Murder House is how obsession can consume a person, driving them to desperate and dangerous acts. Hayden's girl-on-girl crimes against Vivien are vicious and hard to watch. The only thing certain about Hayden is her actions are completely unpredictable.

Larry Harvey

American Horror Story Murder House Denis O'Hare

Harvey (Denis O'Hare) would be completely pathetic if it wasn't for all of his horrible misdeeds. An adulterer who casts his family aside for the comely neighbor, Harvey is driven by lust and greed.

At times he's weak and rendered impotent by just a harsh word, He's also capable of being incredibly manipulative, doing his fair share to drive Ben Harmon (Dylan McDermott) insane and aiding the spirits in the house as long as it means he'll remain near Constance (Jessica Lange). He's a Renfield for this millennium. It's hard to determine if Harvey is more dangerous when doing the dirty work of others, or when he takes matters into his own disfigured hands.

Constance Langdon

Constance Murder House AHS

Constance is pragmatic about the curveballs life throws her, but she tends to overlook how her choices factor into the big picture. She's a murderess, a kidnapper, a thief and a liar, Constance is a woman with many talents who is smart enough to get herself out of sticky situations. She is only honest to be cruel. Although her motives should be transparent, her treacly accent and insistence of good intentions leave room for doubt.

Aside from appearing to fancy herself as some kind of misunderstood martyr is the fact that Constance isn't burdened with much of a conscience. Everything she touches, she destroys which is why her interest in the Harmon family foreshadows their bleak end.

Tate Langdon

Evan Peters as Tate Langdon in American Horror Story

A bad seed even before darker forces take hold, Tate Langdon (Evan Peters) is as dangerous in the afterlife as he is alive. Beautiful on the outside but rotten to the core, Tate's attempts at self-improvement never yield a positive result. A mass murderer and rapist, Tate's sensitive side is tempered by his sadistic tendencies whether it's goading Dr. Harmon with tales of sex, lust and self-satisfaction involving Harmon's daughter, Violet, or his inclination to stick a fireplace poker up the rear of one of his victims.

Some of the season's most chilling moments involve Tate's exploits: donning the rubber suit to rape Vivien, painting his face to resemble some kind of angel of death before gunning down his classmates and lighting his stepfather on fire.

NEXT: 10 Most Terrifying TV Shows You Shouldn't Watch Alone On Halloween, Ranked