Jackson's alter ego is Holt Hyde, known as DJ Hyde in the Monster High books; his transformation is triggered by heat in the book and music in the movies or webisodes.
Jackson is friendly and likes to play casketball, though he has a geeky fashion style and is sometimes picked on by other students. He appears to be the only human student at Monster High, and he is confused by his normalcy and feels a bit outcast in a school full of monsters.
In the diaries he once asked Draculaura to bite him,1 as he was afraid they couldn't really be friends when school started. Draculaura was able to talk him out of it, but she could tell he was still depressed.
In the Monster High book series he is not afraid or uncomfortable about being around monsters and is able to interact with them quite easily. Draculaura noted in her diary that he was unfazed when he met her father, who normally creeps out both human and monsters.
In the cartoon, he seems much more wary around monsters, most likely due to being bullied at school for being a "normie". He even went as far as to say that he "didn't belong", and that no one would want him at Cleo's party in the webisode "Hyde and Shriek".
While the Monster High students are unaware of Jackson's/Holt's dual nature, older monsters can apparently sense his duality. This is evident in Draculaura's 'Basic' diary when she overhears a conversation between her father and Jackson, where Jackson makes a light joke about stakes. Her father later cryptically tells her that Jackson is more than he appears.
Jackson has black hair with blonde ends, blue eyes and a pierced left eyebrow. He has a yin yang symbol between his shoulders. Because he is shy, his body language is nervous and he tends to hunch his shoulders.
Jackson, and therefore Holt, has a Yin-Yang tattoo on his back at the base of his neck.
Throughout each storyline, Holt and Jackson have no control over their transformations and change from one into the other under specific circumstances. In the cartoon series, it seems to be music that causes Holt/Jackson's transformation. This is first seen in "Hyde and Shriek." In the books it is heat.
In Holt Hyde's Basic diary, Holt's transformation into Jackson Jekyll normally occurs at sunrise and lasts until sunset. Holt noted that when he was trying to see what the town was like during the day, he blacked out at the moment of sunrise. However, in Jackson Jekyll's Basic diary, it's revealed that the trigger for Jackson's transformation has since changed, so that it is now music as in the cartoon. Specifically, "music with a 4/4 time signature played in excess of 90 decibels" triggers the transformation into Holt. However according to the dairy, because of Jackson's "elemental heritage + hyde transformation + teenage boy" status, it is likely to change again at least once more before he hits adulthood.
In the Monster High book series, the change is caused by temperature shifts, be it from him getting hot from embarrassment or from outside forces like a hot day.
There are times when Jackson's and Holt's memories and abilities leak over to the other. For example, in the diaries Jackson is able to keep up with Deuce Gorgon in a basketball game (to the Gorgon's surprise), while Holt recognizes Draculaura at a club despite the fact it's the "first" time he meets her.
Jackson Jekyll/Holt Hyde is the son of Dr. Jekyll and Mr. Hyde. Maintaining the trend of classic movies, there is a 1931 version of Dr. Jekyll and Mr. Hyde, released by Paramount, directed by Rouben Mamoulian and starring Fredric March.
The story of Jekyll and Hyde is based on a horror tale by Robert Louis Stephenson, Strange Case of Dr Jekyll and Mr Hyde.
In this story, a scientist devises a potion that will separate his evil, base nature from his normal self. The result is that while his regular self, Dr. Jekyll, remains human (both good and evil), his evil nature forms a new personality, Mr. Hyde; both occupy the same body.
Eventually, Hyde becomes more and more out of control, and Jekyll knows that some day he will take over the body completely.
While many movies portray Hyde as being monstrous in appearance, in the book he merely looks sinister, and is short.
The influence of these characters on the appearance of Jackson Jekyll is clear in that he has many elements of duality or being patched together: his hair is two colors, he has a yin-yang tattoo, his clothes tend to be halved or made of patchwork.
The original Henry Jekyll portrayed as a scientist; Jackson follows suit on a visual level as he is dressed as a studious "nerd".
In Monster HighEdit
In the Monster High books, his mother is named Sydney. The exact way Jackson's family tree looks is fuzzy at the moment. In Jackson Jekyll's diary, it is revealed that it's Jackson's mother from whom the dual nature comes, while his father is revealed to be a fire elemental and implied to be the parent through which Jackson is the cousin to Heath Burns, a fact first mentioned in "Fear Pressure". However, Ghoul Spirit states that Jackson's mother is the sister of Heath's father, making the exact familial relations unclear.
Until he was 16 years of age, Jackson did not know he had a monster half in the form of Holt. He did know both his parents were monsters, but he thought he'd only been given his mother's human side. Neither his parents apparently thought their son's dual nature was something they needed to inform him about.
Especially Jackson's mother is very protective of her little boy, and seeing him get hurt is something that can trigger her transformation into the mode most suited for helping him out. Also according to Holt Hyde's Basic diary, Jackson's mother doesn't keep the same job for long and the family regularly moves to a place closer to her new job.
In the Monster High books, Jackson is regarded by Holt as his brother, as the latter reveals to Melody Carver: "Because DJ likes her. I can't do that to him...or me, or whoever....He's kind of like my brother, I guess." Heath Burns is not related to Jackson in the books, and Jackson's father is absent, leaving it unclear how much of conventional canon is canon for the books.
- Deuce Gorgon - In the diaries Jackson met Deuce at their neighborhood casketball court. After Jackson surprised Deuce by playing well, he cemented the friendship by lending Deuce his sunglasses. In the cartoon, Deuce was the one to convince Heath not to "stonewall" his cousin and more or less has Jackson join his circle.
- Draculaura - In the diaries Jackson and Draculaura live on the same street, and Draculaura brought a pie to his family. He returned the empty pie plate to her house, and impressed Draculaura by not being afraid of her father, and even cracking jokes. He later asked Draculaura to turn him into a vampire, but she refused (then she explained to him why she became a vegetarian). She later brought Jackson to Clawdeen Wolf's and her family's annual "Boo-B-Que."
- Frankie Stein - In the webisode "Miss Infearmation", Jackson meets Frankie. Jackson was being bullied by Manny Taur and Frankie jumped in and stopped the bullying. This began a possible attraction storyline arc for Frankie and Jackson. When Jackson and Frankie first shake hands, a cloud formed by an electrical shock from Frankie momentarily forms the shape of a heart. Outside of an impromptu party at Cleo's house, Jackson agonized over going in because he felt he didn't fit in. But the thought of Frankie being there seemed to be the one compelling factor for him, so it seems Frankie has started to have some impact on him. Later, at the party, she also hits it off instantly with Holt Hyde, who seemed quite taken with her as well, going so far as to compliment and flatter her, illustrating that certain things can carry over from one personae to another.
Clair - In "Ghouls Rule", Jackson meets this gothic girl in the hallways of the normie school, and the two become friends overnight. She helps keep trouble away from Jackson, and even helps the Ghouls of Monster High reunite in friendship with the normies. By the end of the film, it seems as if she wants to be more than friends with him, going as far as to kiss him at the Halloween Party.
Jackson's pet is Crossfade the chameleon (like Holt Hyde), only in green form.
Draculaura writes in her Basic diary about her crush on Jackson, and her interest seems to be reciprocated. However, in her School Out diary she writes that the two of them "split up" because Jackson never showed up for any of their dates in the evenings (as by that time he would have changed into Holt Hyde), and could never remember why the next day.
Starting in the webisode "Miss Infearmation", he and Frankie Stein have displayed big feelings for each other. Since then his feelings for her have grown and he seemed disappointed when Frankie tells him they can't go out yet until he works things out with Holt Hyde. However, they are still close friends and he doesn't seem to mind waiting for her.
In the novels he is dating Melody Carver, but in the first novel Cleo kissed him to get back at Melody for bumping into her, causing her to spill her grapes, which (along with the fact of Melody not knowing about DJ Hyde) caused some tension between the two of them.
In "Ghouls Rule", Jackson begins scouting out the normie school, and there meets Clair. The two become fast friends, and by the end of the film, maybe even some thing more, with Clair kissing him at the Halloween Party.
Story of Joining Sora's TeamEdit
During Lock, Shock, and Barrel's mission in Monster High, they pranked each student of Monster High, but the only ones they haven't pranked was Jackson Jekyll and Twyla, because of how Manny Taur bulllied him and how he only gets invited to parties because he and Holt share the same body. And Twyla was a very shy ghoul and showed the trio kindness. So the trio began to persuade Jackson and Twyla to join the team and become friends. After Jackson and Twyla accepted, music was turned on from the school party and Jackson turned to Holt Hyde. Holt then ratted the trio out and the students began to surround them. But right when everyone was going punish the trio, Heartless, Nobodies and the Unversed were about to attack [[Draculaura and Ghoulia Yelps. But before they did, the trio moved the ghouls and took the fall, and the students saw the trio fighting the REAL enemies. Lock took down the Heartless, Shock took down the Nobodies, and Barrel took down the Unversed, and as the battle ended, Draculaura and Ghoulia were thankful to the trio for saving them. But when Lock, Shock, and Barrel fainted, the students nursed them back to health. As the trio woke up in the nurses office, they were confused of why Frankie Stein and the ghouls nursed them back to help, and as the students explained, they were all forgiven and the trio explained about the Heartless, Nobodies, other worlds, and Master Xehanort, the students were shocked about their world about to be consumed in darkness. Then after Sora, Kairi, and Riku came in the nurses office from the Gummi Ship to bring the trio back to the ship, the entire Monster High student body asked to join. Just when they asked, Lock, Shock, and Barrel asked also, and said that they'd be big help, and just as Sora, Kairi, and Riku disgused it, they all agreed and the students joined the team.