Frankie Stein is a 2010/2016-introduced and all-around character. She is a simulacrum, specifically the daughter of Frankenstein's monster and his bride, and a student at Monster High. Having been born as a 15-year old only recently, Frankie has all the intelligence and physical capabilities of her born-age, but none of the appropriate life experiences. She has been rapidly gaining ground, though, mostly with the support of the close group of friends she created around herself. In everyday life, Frankie has an unrelenting positive disposition, which allows her to easily make friends and motivates her to always look for solutions that help out as many people as possible, but it also makes her prone to being taken advantage of. It doesn't help that she is a bit clumsy either. Befitting her heritage, Frankie has an interest in a broad range of scientific subjects and favours the practical side over the theoretical one. This interest extends to sewing and cooking, both skills she excels at and has utilized to create other simulacrums.
Frankie is originally voiced in English by Kate Higgins. The "Zombie Hero Girl" who represents Frankie in the Fright Song music video is portrayed by Angela Duscio. Frankie's singing voice in "New Ghoul @ School" is by Allison Iraheta, though it may be lip-sync and is only in a cutaway fantasy scene.
Frankie Stein is a wholehearted, and pretty-in-personality kind of girl. She is optimistic, positive, kind-hearted and always gets along with others, although she is naive. Frankie is aware of her flaws and embraces them. She loves her friends and they are the most important monsters in the world to her. She is nice and outgoing, and likes to try new fashion styles. She can sometimes struggle with her quirks but always finds a new perspective of her quirks in the end. She is portrayed as kind and naïve, but her naïvety or naïveté, makes her unaware of average teenage life, and uses source on teenage "unlife" or "teenage lives" through magazines; though what she looks up to is never actually accurate to how things really are in real life or to the situation she's in.
Frankie is best friends with Draculaura, Clawdeen Wolf, Cleo de Nile, and Lagoona Blue. (In the Generation 1 cartoon, she is also friends with Ghoulia Yelps). She enjoys spending time and company with her friends, and sometimes goes shopping with them. Ghoulia Yelps is replaced with Ari Hauntington at the end of the movie: "Welcome to Monster High: The Origin Story", and in the Generation 2 webisodes, she is replacing Ghoulia. Either that, or she is not absent from the reboot series and Ari is just filling in for now. Even though it may appear she is absent from the reboot series, Abbey Bominable is also a close friend of Frankie's, and so is Operetta, who is also not absent from the Generation 2 series. There is confirmation that no one in the reboots is being replaced.
When Frankie first met Abbey, she saw Abbey as a nuisance due to the fact of which she believed the latter threw a snowball at her. She finds out the truth in "Frost Friends" that it was actually Toralei , to which Toralei Stripe got the revenge-payback she deserved in said webisode. Frankie is also kind, outstanding, and awesome! She is an optimist who believes anything can happen and doesn't give up in the face of adversity.
Frankie has light-green or mint-colored skin. She has long, straight, white, hair with black streaks, and stitches on her neck, arms, legs and a smaller, stitched scar on her right cheek, as well as two small bolts on her neck. She has mismatching eye colors, her right being a clear blue and the left a bright green. According to the webisode Department of Monster Vehicles in volume 3, she is 5 ft. 7 in. in height. In the Lisi Harrison books, she has solid black hair which she puts in white streaks later for the school Monster Mash dance in the first book, Monster High. She wears blue skull earrings, a black spotted tie, a green and black square top with a white upper top with round short fishnet sleeves, she wears a black belt, with silver chains, and a silver lightning bolt on top. She has on black and white ankle strap heels, red nails, and a bracelet.
She usually wears schoolgirl fashions, as both Monster High the original and Monster High Generation 2, but in the movie: "Welcome to Monster High", she wears a headband with her rebooted Generation 2 outfit which is an electric-blue, lightening-bolt-designed headband, and has silver highlights or silver streaks in her hair along with her black streaks. She also typically wears a metal-board-like metal-clip as a hair clip or barrette in the back of her hair in the middle of her head, middle of her hair. Sometimes, Frankie’s hair would be tied up in a ponytail or kept in a beehive.
Frankie was born in a lab created by Frankenstein's monster and the Bride of Frankenstein's monster. She started out as 15 days old, being the youngest student at Monster High, and then after, gained to be 16 days. She made friends with Draculaura and Clawdeen Wolf. Later on, she met Lagoona Blue, and got to be friends with her, too. She also got to be friends with Cleo de Nile at the end of "New Ghoul @ School". Frankie has made many friends since then, such as Deuce Gorgon and Clawd Wolf. She also made friends with Gillington Webber.
Frankie made friends with Andy Beast. She also made friends with Finnegan Wake , and Neighthan Rot, Bonita Femur, Sirena Von Boo, and Avea Trotter. She has made many friends and has been a student at Monster High since. She also made friends with Isi Dawndancer in "From Fear to There Part 2". In the Monster High book series, she is created by Viktor Stein and Viveka Stein as they are her parents and she is the granddaughter of Frankenstein's monster and his bride. In the series of the Lisi Harrison books, like all series, she is 15 days old. She is new to the world, and makes friends with Clawdeen, Blue, Lala, and Cleo, and also Melody Carver and Billy Phaidin, who are also fellow RADs, though Melody appears as a human at first.
Starting out at 15 days old, Frankie is the youngest student at Monster High. She was built a while back, and on the back of her Picture Day box as in doll box, she says "How many days has it been?". As of Welcome to Monster High, her age is "115 days old. But some parts... are older than others".
There is a generational distinction between Frankie's parents as they appear in the Monster High book series versus the rest of the franchise. In the Monster High books, which are the only source of a name for Frankie's parents (Viktor and Viveka Stein), the two are creations of Frankenstein's Monster and the Bride. This makes the original Monster of Frankenstein (usually referred to as just Frankenstein) Frankie's grandfather and his Bride Frankie's grandmother, while Victor Frankenstein is thus her great-grandfather.
Generally in all versions of Monster High, except for the Lisi Harrison books, Frankie is the daughter of Frankenstein's monster and the Bride of Frankenstein's monster, and thus also the granddaughter of Victor Frankenstein. In the Monster High Diaries, Frankie's parents are only referenced to as Mr. and Mrs. Stein. Frankie's mother was the second monster created by Victor Frankenstein and her father was the first. Frankie lives with her parents and loves them, but she does not always agree with them or their opinions.
Every time she walks downstairs for breakfast in the morning, her father insists on screaming: "It's alive!" much to her dismay. This is also available in the Lisi Harrison books where her father is instead Viktor Stein and does the exact same thing.
Frankie got her black-streaked white hair from her mother (in this sense meaning her hair was inspired by her mother rather than getting it genetically, as she was built rather than born), who wears her hair up in a high "beehive." This may not be canon to the book series, as Frankie's hair is solid black and her mother is Viveka Stein; however, it may still be true as Viveka's hair could also be black.
In Hoodude Voodoo's 'SDCCI' diary, the character Hoodude claims that Frankie's father created his wife, Frankie's mother, to which is a different story in the original monster story, to where the mad scientist Victor Frankenstein had created the Monster's bride by a request of the monster himself.
Her parents are kind and warmhearted to her, being very kindhearted parents overall, but, like all parents, they set limits. Frankie, overall, has a good and healthy relationship with her parents. In the Monster High junior novels or junior novels, it is unknown whether or not the parents are Viktor and Viveka, but they are definitely Frankenstein's Monster and the Bride of the monster themselves.
In the webisode series, the Monster of Victor Frankenstein is the owner of a lab in the Monster High Catacombs, when in HooDude VooDoo, Draculaura refers to the character as "Frankenstein", his most common and more popular name in popular media and popular culture, but he shouldn't really have a lab since, in accuracy, "Frankenstein's Lab" belonged to the human creator Victor Frankenstein (The literary victor named his first monster Adam, as he was the first artificial man).
Hoodude Voodoo may or may not be considered a family member since Frankie created him.
In Frankie Stein and the New Ghoul at School, Frankie built a little sister named Zappit, but outside the book Zappit is never mentioned again. She most likely got retcoined, as in generation 2 Alivia Stein is introduced.
Alivia Stein is Frankie's little sister introduced in part 2 of the Howliday special. although Alivia wasn't how Frankie wanted her to be, she still loves her. Her eye colors are opposite of Frankie's and her bolts on on her head.
Frankie is friends with Draculaura, Clawdeen Wolf, Cleo de Nile, Lagoona Blue, Ghoulia Yelps and Deuce Gorgon. In the reboot of Monster High or the Monster High Generation 2, she has not made friends with Ghoulia as of yet. This fact remains to be seen until Ghoulia makes an appearance in the reboot. She is not very close with Deuce Gorgon in the movie "Welcome to Monster High", as he does not get a big enough role in the movie. She does however still have Draculaura, Clawdeen, Cleo and Lagoona as friends. She is also most notably friends with Jackson Jekyll, with whom she has a love interest in within the cartoon series.
Frankie has a history to having many crushes on at least 3 mansters, but nothing too serious as of yet. In the cartoon, she was dating Jackson Jekyll and Holt Hyde until she broke it off due to their conflicting personalities. She also had created Hoodude Voodoo as a pretend-boyfriend just to impress her goulfriends (Though Clawdeen is also not in a relationship, as in 'HooDoo You Like?', Clawdeen only talks about Draculaura when she is not there in the conversation, as the latter is only Clawdeen's friend and is even dating her friend Clawdeen's brother). In Lisi's books, she fell in love with Brett Redding, but he has an overprotective girlfriend, Bekka Madden. Brett soon breaks up with Bekka and starts dating Frankie later on in the books, but Brett later breaks up with her. Frankie also had a crush on Neighthan Rot in Freaky Fusion which is mutual, but they never actually dated. According to the doll diaries in her 'School's Out' diary, she once had a crush on a Scottish gargoyle football player who is called by or goes by the number on his football jersey uniform "7". Also in the books, a friend named Billy Phaidin (not to be confused with Invisi Billy) has a crush on her, but it is unrequited and Billy (nicknamed InvisiBilly) starts dating Spectra Vondergeist in the books later on. She once had a small crush on Deuce Gorgon, according to 'New Ghoul at School', but it was completely one-sided, because he loved Cleo, and Cleo soon thought he was cheating on her when Frankie says that Deuce is her boyfriend. This mistake is later fixed at the end of the TV special. In the books, D.J. Hyde has a crush on her, but by the second book, he tells Frankie that he wants to move on.
For the main series, she has a pet dog-looking creature named Watzit who hates being called a dog and who is made of many different parts. He is said to "bark like a dog, meow like a cat, tweet like a bird and eat bananas like a monkey" while Watzit also is a tan-and-dark-brown colored pet who has the appearance of a small dog, has heterochromic eyes like Frankie, same as also, the left green and the right eye blue; while he also possesses a pair of grey wings and has dragon spikes on his body. In the Monster High books by Lisi Harrison, Frankie has a set of pet rats known as the Glitterati, who help her with her daily morning routine, while the rats are also seen in "New Ghoul @ School" and also "Fright On!".
- Electrokinesis: Frankie can create and control electricity, either accidentally or on purpose. Through her bolts, when she gets emotive, or through her body, mostly through her hands, Frankie can charge anything or shock anyone. She herself can be charged too, either by the Recharge Chamber from "Freaky Fusion" or simply by random flashes of electricity and lightning bolts.
- Magnetism: In "Bad Scare Day", it is shown that, when her two bolts are switched from one side to the other, reversing her polarity, Frankie can attrack objects with magnetic proportions.
- Pyrokinesis: Frankie can create fire at times too, mostly due to her electrokinesis. She can do this by beaming electricity at flammable materials or by simply rubbing her hands.
- Chronokinesis: In "Boo Year's Eve", Frankie was able to stop time accidentally, but then rewind certain people's actions, confirming then Frankie's ability to control time. Why she would have such power is unknown.
- Body Separation: Frankie can detach certain parts of her body and control them at distance, which she frequently does with her hand to reach tight places.
- Sewing: Due to being a monster made of various detached body parts only connected by stitches and strings, Frankie has developed a skill on sewing and tailoring, which is not only one of her favorite hobbies, but it comes in handy in times when her body is dismantled too.
- Life Creation: Like her father and grandfather, Frankie has been shown to creating life herself, such as Hoodude and the gingerbread boy.
Frankie's full name comes from 'Frankenstein', a novel by the romantic period English writer Mary Shelley. It was conceived during a writing contest between her husband Percy Bysshe Shelly and Lord George Gordon Byron, which she won.
- October 23, 2007: Mattel requests the trademark for Frankie Stein.
- May 05, 2010: The Monster High website goes live, featuring Frankie Stein's profile.
- May 05, 2010: Frankie Stein's profile art is revealed.
- May 05, 2010: Frankie Stein makes her animated debut in the Higher Deaducation commercial.
- May 05, 2010: Frankie Stein makes her 2D cartoon debut in Jaundice Brothers.
- Early July, 2010: Frankie Stein's debut doll is released as part of the 'Basic' series.
- Early July, 2010: Frankie Stein makes her diary debut in her 'Basic' diary.
- Early July, 2010: Frankie Stein's debut plushie is released as part of the Friends series.
- September 01, 2010: Frankie Stein makes her Monster High book debut in Monster High.
- February 12, 2012: Frankie Stein makes her 3D cartoon debut in Why Do Ghouls Fall in Love?.
- September 05, 2012: Frankie Stein makes her Ghoulfriends book debut in Ghoulfriends Forever.
- October 22, 2014: Frankie Stein makes her anime debut in "Monster High Life Is Amazing!".
- Frankie's parents are Viktor Stein and Viveka Stein in Lisi Harison's Monster High book series, and she is the granddaughter of the Monster of Frankenstein and his Bride, making Victor Frankenstein Frankie's great-grandfather.
- In Electrified, she mentions she was born in Germany, specifically Bavaria.
- Frankie's eyes are both periwinkle in the books, released to be so in The Ghoul Next Door, where in other adaptions of the Monster High franchise, one is blue and one is green.
- Frankie Stein's license shows she's 5'7. 
- Frankie's birthday is on June 26th, meaning that her sign is Cancer.