|“||There's probably a lesson to be learned somewhere in here about cheating; good thing I don't care.||„|
|~ Stephanie Knightleigh|
|“|| Edgar: Stephanie, don't do this! You don't want our blood on your hands!"|
Stephanie: "Of course I don't- that's why I'm wearing gloves..."
|~ Stephanie preparing to kill Edgar in Frost Bites|
Stephanie Knightleigh is the main antagonist of the Edgar & Ellen franchise. She is the daughter of the wealthy mayoral family of Nod's Limb. In the television series, her villainy ranges from inconveniencing to abusing her rivals: the protagonists Edgar and Ellen along with their caretaker Ronan Heimertz. However, in the Gothic book series, which seemingly takes place after the TV series' chronology, her character is vastly more sinister, engaging in malicious, and often criminal acts including fraud, and even murder.
Her TV counterpart is voiced by Ashleigh Ball.
Despite being a teenaged girl, Stephanie is incredibly intelligent- easily able to influence her father, who in turn, easily influences the town with his mayoral position. She is also incredibly sadistic, taking great pleasure in humiliating her enemies every opportunity she gets. She is a control freak, who's ultimate goal is to have everyone bend to her will, which is why she hates Edgar, Ellen, and Ronan so much, as they refuse to do so.
Apart from hating the Tower Mansion residents, she also hates her genuinely kind younger brother Miles, as he is the only member of the Knightleigh family who seems even moderately capable of helping someone other than himself.
In Crushed Stephanie is seen to be livid when a girl named Ursula goes to the school's dance with Edgar. The reason for this is unclear, but it's possible that she may have (had) feelings for Edgar, which explains her particular dislike of Ellen, who is more important to Edgar then she is. This is yet to be confirmed, however, as Stephanie has also made several attempts on Edgar's life.
The book version of Stephanie is even more sociopathic and less likable; she had no qualms resorting to methods such kidnapping, brainwashing, animal cruelty, torture, and the killings of random people to achieve her duplicitous goals.
Stephanie was a recurring antagonist in the TV series, being portrayed as a snobbish, arrogant young girl who rivaled Edgar and Ellen- as they were the only people in town who she could not manipulate. She commits a plethora of incredibly petty villainous deeds throughout that include, but are not limited to:
- When Edgar and Ellen enter the town's pet competition and oppose Stephanie's pet poodle Duchess, all three of them resort to cheating in order to win. Their efforts are in vain, however, as Pet and Duchess are both incapacitated, resulting in one the judge's toupee being declared the winner.
- Stephanie orders that the twins' house be demolished as revenge for them stealing her porcelain unicorn collection. However, the building must undergo inspection to prove that it's unsafe first. While the house is being inspected, Stephanie fantasizes about murdering the twins with a wrecking ball.
- Stephanie and her friends rig the school play to humiliate Ellen in front of the entire school through a series of pranks. Ellen manages to use them to her advantage to humiliate Stephanie instead.
- Stephanie attempts to destroy the ecosystems of a swampland so she can build an amusement park over it, and is given management privileges over a construction team, which she is seen treating in an extremely condescending and vituperative manner. Edgar, Ellen, and even her brother Miles band together to stop her.
Unlike the TV series, the book series has a continuing storyline about Stephanie's father attempting to build a hotel over Gadget Graveyard, and Edgar and Ellen's attempts to stop it. Stephanie's character is more ruthless in this version.
- In Tourist Trap, Mayor Knightleigh plans to demolish Gadget Graveyard to build a hotel, so Edgar and Ellen steal Stephanie's position as tour guide to scare the tourists away and save the graveyard. After the celebrities are abandoned at the French Toast Festival, a vengeful Stephanie assaults Ellen and the two get into a fight which is broken up when Miles gets stuck in a pool full of syrup.
- In Under Town, Knightleigh's plans to build the hotel continue, despite the twins' efforts, and Stephanie is seen assisting him. She comes across Ellen's favorite sentient carnivorous plant, Berenice, and is disgusted by it. She violently kills Berenice with a shovel, and begins the demolition of the property.
- In Pet's Revenge, Stephanie is forced to invite Ellen to her sleepover after getting into an argument about the twins with her mother. Ellen is abused by Stephanie and her friends the entire night as revenge for their previous altercations, despite Ellen behaving similarly to Stephanie do to her being drugged by Pet, who's tears are revealed to have a brainwashing property. During this time, Ellen manages to befriend Miles, who is the only person nice to her at the Knightleigh residence.
- In High Wire, Stephanie's villainy takes a noticeably darker tone when it is revealed that she formed an alliance with Ormond Heimertz (Ronan Heimertz' cousin, and the technical legal owner of Tower Mansion), an escape art performer for a mysterious circus that has recently arrived in Nod's Limb. Ormond manipulated Edgar and Ellen into finding three amber artifacts, with the intention of selling them so that he can retire early.
- After a failed attempt to frame Ellen for robbery, Stephanie fakes Ormond's death and then collapses the big top, which resulted in the deaths of several guests, and made sure Ronan, along with Edgar, Ellen, and circus performer Madame Dahlia were framed for the crime. In exchange for help in getting the artifacts and disposing of his family, Ormond gives Stephanie the deed to Tower Mansion, effectively kicking the twins out of their home, allowing Stephanie's project to continue over the property.
- In the finale of the first overview, Nod's Limbs, the town's founder, Augustus Nod, is found in a cave after 200 years, having survived from ingesting a healing substance known as "balm," granting him quasi-immortality; much to the chagrin of the Knightleigh family, who view him as a threat to their power. Stephanie then causes a cave-in, in an attempt to kill Edgar, Ellen, Miles, and Augustus, but Ronan arrives and rescues them. Augustus then banishes the Knightleigh family from Nod's Limb, stating that they aren't worthy to lead the town, and the Knightleighs move to another town called Smelterburg. Stephanie is sent to a boarding school by her parents as punishment for her actions.
- In Hot Air, Several months after the events of Nod's Limbs, Edgar and Ellen have been praised as local heroes for saving Augustus's life, however the townsfolk begin to tire of their constant pranks, such as when a swarm of rats ruin the mayoral election, and Benedict's journal entries are stolen, which provides details about the location of the balm springs. The twins realize that Stephanie has escaped the boarding school, and that she is behind the recent disasters.
- In Frost Bites, Stephanie, with Ormond's assistance, kidnaps and hypnotizes the Midway Irregulars, the youngest members of the circus troupe, by drugging them with Pet's tears. Stephanie orders them to murder Edgar and Ellen, and capture Pet so that she can torture him and harvest his tears. She also plans to have them mine more balm for her to sell to the highest bidder. The twins have been tracking her down to bring her to justice, but Stephanie and her accomplices manage to drain an entire balm spring and destroy it, separating everyone, and allowing Stephanie to escape.
- In the finale Split Ends, Edgar, who can't find Ellen after the events in Frost Bites, manages to free the Irregulars and subdue Ormond, the latter almost succeeds in getting Edgar killed by a hypnotized Ronan until the latter left them due to the "new orders" that Stephanie had given him behind Ormond's back, and Ormond is dragged away and presumably killed by the Irregulars. Stephanie, however, remains at large.
- She is voiced by Canadian actress Ashleigh Ball, who also provided voice work for Aspheera from Ninjago, Hansel from Black Lagoon, and Queen Chrysalis while she was disguised as Applejack.
- There is some debate as to whether or not the book series and television show take place in the same universe. Stephanie's out-of-character behavior would imply that they don't, but this issue has yet to be addressed by the authors.
- There is a repeated mention to a mysterious incident involving Stephanie, Ellen, and claw hammer that resulted in Ellen's pinkie fingernail being disfigured.