|“||Mommy, are we going away because I'm not a monster?||”|
— Dennis asking Mavis why she wants to move
He is also the grandson of Dracula and Martha (his maternal grandparents) as well as Mike and Linda (his paternal grandparents). Through Mavis, Dennis is also the great-grandson of Vlad (his mother's paternal grandfather).
While born showing no vampire traits, by his fifth birthday, he finally grew his fangs and likewise manifested his vampire abilities. Dennis is kind, innocent, funny, silly, shy, odd, cowardly, hyperactive, loveable, and different but at the end of the film, he becomes brave, silly, hyperactive, optimistic, kind, funny, modern.
Dennis is a little boy with unruly, striking red hair and blue eyes, a combination of genes he inherited from both his parents. He is dressed in a sports jersey with the number "4" on it and shorts similar to Johnny. According to creators, Dennis inherited Mavis's striking eyes and pale skin and Johnny's bright hair. After manifesting his vampire traits, his baby canine teeth fell out to reveal his adult teeth as vampire fangs.
Dennis is outwardly portrayed as being optimistic and childish such as any child his age. He appears to have a fairly similar temperament to Johnathan: easygoing, insouciant, and exuberant in most scenarios. Aside from his high-spirited demeanor, Dennis has substantiated noticeable signs of maturity for his age - even as a five-year-old he finds himself too old for any childish needs Mavis attempts to provide him with. Overall, he is rather naive about certain things; he expressed a large amount of naivety when he lacked any sort of monstrous abilities. Initially, Dennis is unaware that his apparent lack of vampire skills was an immense problem and would impact him negatively; when he is exposed to the realities of the world, Dennis began taking this fact more seriously, attempting to become a vampire in order to remain at Hotel Transylvania.
Dennis was born 2 years after the events of the first film (June 13th, 2013) to Johnny and Mavis and lived with them at his maternal grandfather's hotel. According to Mike (his paternal grandfather) Dennis was named after Mike's father (a great grandfather).
According to the height chart, "DENNiS 1 YEAR!" was taller than "Mavis year 1", but "DENNiS 2 YEARS!" was not as tall as "Mavis year 2".
As he showed an apparent lack of vampire traits, he was raised mostly human, being fed healthy foods and taught by his parents. He often played with the Werewolf kids, and he loved to watch Kakie The Cake Monster's show.
Due to his heritage and possibly his young age, Dennis shows no signs of becoming a monster, much to the distress of Dracula. Dennis' apparent lack of powers seem to be because he looks more human like his father than his vampire mother.
Monster Training Boot Camp
After Mavis and Johnny head to California to visit Dennis' paternal grandparents, Mike and Linda, Dennis is left in the care of Drac and his friends Wayne, Murray, Griffin and Frank. Though, unknown to Mavis, Drac, wanting to bring out Dennis' monster genes, decides to recruit his friends into putting the little boy through a monster training boot camp.
First, Drac had Frank show Dennis how to scare people by jumping out and scaring two joggers. However, the joggers recognize Frank and ask to take a selfie with him instead. Dennis tries to jump out and scare them, but they just think he's adorable. Next, Drac has Wayne show Dennis how to eat an entire deer, but Wayne, being the old wolf, forgets how to attack the deer and instead chases a frisbee a nearby human threw for his dog. Finally, Drac asks Murray to conjure up a huge sandstorm to show Dennis how to be a ruthless monster. However, as Murray is performing his spell, he throws out his back and only summons a small amount of sand in which Dennis begins to play in and makes a snowman out of the sand.
When all else failed, Drac decided to take Dennis to his childhood camp, Camp Winnepacaca, where he learned how to use his vampire skills as a kid. However, the trip did not help Dennis as the camp was under new management, and was "too safe". Drac throws Dennis off a tower to teach him how to fly, but Drac has to save Dennis from falling to his death. The tower collapses under the combined weight of Griffin, Wayne, Murray and Frankenstein's monster, setting the camp on fire. Mavis was extremely mad and upset when she heard what Drac had done and felt that Drac had betrayed her trust (she had placed Dennis under Drac's care while she went to visit Johnny's hometown). Mavis then decides it would be best for them to move following Dennis's party.
When Vlad comes to the party after being invited by Mavis, Johnny has to don a vampire costume. Vlad exclaimed that Johnny's wig looked like "his great-grandma's boobies", but seemed to believe the facade. Upon learning that Dennis was a late-fanger, he volunteered to help Dennis to grow out his fangs. He explained that what he needed to do was take something that Dennis found sweet and innocent (Kakie) and twist it into something terrible. Vlad possessed Kakie the cake monster mascot during his performance to see if Dennis' fangs would pop out, but was interrupted by Dracula as he saw what a traumatizing effect it had on Dennis.
Dennis becomes upset over the arguments between the adults and runs into the woods. Winnie follows him and leads him to her hideout. Bela, who had discovered that Dennis has human blood, tried to kill Dennis, but Winnie got in the way. Bela hits her and Winnie whimpers on the ground. Dennis was enraged and his fangs finally popped out, finally revealing his true life. He quickly turns into a bat and fights Bela, followed by super strength, super speed, and enhanced vision which allows him to be able to see that Bela's gang was coming. After Dennis and the rest of the group defeat Bela and his army, Dennis asks Drac if he's cool now. Drac reassures Dennis that he was always cool, and that he is perfect no matter what.
Then Dennis and his family go back to the hotel to continue finishing his 5th birthday party. Dennis is seen dancing with his father Johnny, his mother Mavis, and Winnie. Dennis then freezes Linda in place. Dennis is last seen dancing some more with Winnie. Just then, Dennis sees his birthday cake and flies up to blow the candle out on his birthday cake. However, just as he about to blow out the candle on his cake, the Elderly Gremlin eats his entire cake, which stuns Dennis as the Elderly Gremlin says she didn't do it.
Family and Friends
Mavis is Dennis's mother. She's shown to be very protective of her son, such as making her dad babyproof the entire hotel and even going so far as to consider moving out of the hotel to a place that would probably be safer for Dennis to live (unaware that Johnny, like Dracula, is against it, and also that Dennis is against it too). Due to Dennis's human heritage and apparent lack of any monster abilities, she only feeds him healthy human food, mostly avocados, and has him sleep most of the night. She first appears in the second teaser trailer for the second film putting Dennis to bed when Dracula pops up, saying that the lullaby she is singing is incorrect.
Jonathan is Dennis's father. Johnny cares for his son like any other father would, but still maintains his slacker attitude. In contrast to Mavis, who inherited Dracula's over-protectiveness, Johnny's concern is on a normal level; such an example is that Mavis freaked out over Dennis losing a baby tooth, while Johnny was more optimistic and congratulating. Due to how much he loves living at the hotel (which doesn't require him to have an actual job to provide for his family), Johnny is willing to cooperate with Dracula to train Dennis as a monster. Unbeknownst to both is that Dennis loves living at the hotel just as much, and hates the idea of leaving.
Martha is Dennis's maternal grandmother. Due to the fact that Martha got killed by a mob of angry humans when Mavis was a baby, Dennis never met her. She was mentioned by Dennis when he asked Dracula if he missed her.Dracula, was. So, Vlad tries to "scare" Dennis's fangs out by possessing Dennis's favorite monster, Kakie the cake monster. Vlad, at first, rejects Dennis for accepting what he is (half-human/half-vampire), but after being called out by his son and granddaughter and helping Dennis and the rest of their friends and family fight off Bela and his cronies, he accepts Dennis for who he is and apologizes for putting so much pressure on him about his fangs, noting how as he gets older, all of his teeth will eventually come out (revealing that his own teeth are now dentures).
In the second film, it is shown that Dennis has a nephew/surrogate uncle relationship with his Grandfather's friends. Similar to Mavis, Drac's friends don't seem to think it's big deal that Dennis hasn't shown any monster abilities, since Dennis is technically half-human, so even if he does have any monster abilities, it will probably be a little while before they show.
One example of Frank, Wayne, Murray and Griffin's concern for Dennis's safety and well-being is when Drac tossed Dennis over the tall tower to try and get him to fly during his monster training. Until Drac actually went in to save Dennis (once it became apparent that he wasn't going to fly), the guys kept noting that Dennis wasn't flying and urging Drac to go and save him, especially when Murray pointed out that Dennis was getting too close to the ground.
Wayne and Wanda's well-behaved daughter. She is Dennis‘s best friend, though she considers him her zing. Her normal greeting is pouncing on Dennis and licking him. She considers him the kindest boy she knows due to her unruly brothers usually causing havoc and chaos. Dennis claims that they are just friends, but despite this, it's possible that he likes her more than a friend as seeing Bela hurt her was enough for him to gain his vampire abilities and defend her.
Mike and Linda are Dennis's paternal grandparents. They love Dennis, but like their daughter-in-law, Mavis, Mike and Linda wonder if Hotel Transylvania (and, by extension, Transylvania itself) is a safe place for Dennis to live in, mostly due to his lack of monster abilities. Linda is a little cautious of the vampires at first while Mike is cynical, but they become more accepting and proud of their grandson’s monster heritage after taking off their zombie makeup.
- "Me, me, like a superhero!"
- "Bleh, Bleh, Bleh!"
- "I love monsters. Video, video!"
- "Mommy, I'm too old for lullabies."
- "Papa Drac, do you miss Grandma?"
- "Mommy, I flew!"
- (Trying to turn into a bat) "I'm a bat... I'm a bat... I'm a bat! I'm a bat!"
- "I got a candy!"
- "Who's in a monster?"
- "That sounds mean."
- "I'm scared, Papa. What's happening to Kakie?"
- "Cebause I'm Batman; to the bat mobile!"
- "You're the coolest guy who wears a cape, Papa Drac!"
- "Are we bad guys papa Drac?"
- ”Hey Daddy Who’s the man with the funny face?”
- Due to his heritage as the son of a vampire and a human, Dennis is a Dhampir, a half-vampire/half-human hybrid; however the term was not used in the second film.
- He is the only hybrid so far in the series.
- Dennis, as a human/vampire hybrid, is able to consume both human food and monster food, although he is mostly fed human food by Mavis.
- Dennis' favorite superhero is Batman.
- In the sequel, Dennis is a main protagonist.
- He's named after his paternal great-grandfather (Mike's father).
- With the exception of having blue eyes and pale skin like his mom, Dennis looks just like his dad.
- As a baby, Dennis was taught the words "Bleh, Bleh-Bleh" by his mother to annoy Dracula, and they were his first words.
- While having grown his fangs and likewise showcased various vampire abilities, it is unknown if he also inherited the vampire-traits of slow-aging and immortality as he is still technically half-human. However, given how many abilities he instantly manifested and likewise quickly adjusted to, it is likely that he is immortal, or at least possesses a very long lifespan.
- Dennis' vampire name by Dracula, Denisovich, is considered Russian by fans.
- Dennis' hair was originally going to be a lot larger. However, the animators had trouble with animating all the hair, and found it to look awkward when Dennis was being hugged or held by people.
- Dennis strongly resembles Harris, Hamish and Hubert from Disney Pixar's Brave. He also resembles Dil Pickles from All Grown Up.
- Dennis (being half human) does not burn in daylight, but he dislikes the sunlight and prefers nighttime. This is likely due to his vampire heritage. It is possible that him being half human allows him to also resist certain vampire weaknesses.
- In some concept arts, Dennis' shirt originally had the number 7 before it was changed to 4.
- Dennis often mispronounces "because" as "cebause."
- It's shown that he and Winnie have a crush on each other. This is seen when Winnie pounces on him and licks him, and when Bela throws her to the ground, it enrages him and causes him to gain his vampire abilities. Winnie is older than him, although they are both children.
- His favorite TV character, Kakie, is a parody of Cookie Monster from “Sesame Street”.
- It is unknown if he has a reflection or not.
- Dennis was born on Friday the 13th.
- Dennis is shown to be ticklish when the guys were trying to be back at the hotel before his parents get there, Dracula tickles Dennis‘s tummy and sides.