Halloweentown High (also known as Halloweentown III) is a 2004 Disney Channel Original Movie released in October 2004 for the holiday of Halloween. This is the third in the Halloweentown series. It is also the last Halloweentown film to feature Kimberly J. Brown as Marnie Piper and to have Sophie (Emily Roeske) in it.
A year after the previous movie, Marnie Piper prepares to begin a new school year in her new home. She asks the Halloweentown Witches' Council to work toward openness between Halloweentown and the mortal world. She proposes to bring a group of Halloweentown students to her own high school in the mortal world. The Council is initially apprehensive about this, mostly due to the legend of the Knights of the Iron Dagger: a fanatical knighthood who wanted to destroy all things magical. The Council, however, agrees to accept the plan after Marnie mistakenly bets "all the Cromwell magic" that her plan will work . If she does not prove she is right by midnight on Halloween, then her entire family will lose their magical abilities.
The Halloweentown students consisting of a witch, a warlock, a werecat, a werewolf, an ogre, a pink troll, a fairy, a zombie and a gremlin arrive. They are magically given human appearances to disguise their true non-human natures. School begins with Marnie acting as tour guide for the exchange group ("from Canada"), Aggie substitute teaching so she can be available in case of need, Cody, a new student, showing a romantic interest in Marnie, and a possible threat to the school from the Knights of the Iron Dagger. She encourages the kids to join sports teams and clubs.
While Aggie proves unable to teach any subject effectively (she keeps letting her magic take over: she conjures up a parrot in science class, and later we learn that a llama was produced, one kid was turned into a lamp post, and another lost one of their ears), the Halloweentown students keep to themselves, hiding in the refuge that Aggie magically creates for them in a remote student locker. Marnie gradually encourages the kids to join school activities and make new friends.
Marnie's progress is interrupted by a warning that appears to be from the Knights of the Iron Dagger, then by a magical incident at the mall that results in the Halloweentown students assuming their natural appearances, by a break-in at the secret magical locker, and finally by the disappearance of one of the students.
Meanwhile, Marnie's developing relationship with Cody parallels an unexpected romance beginning between Aggie and the school's principal, Phil Flanagan. Aggie suspects Cody of being the cause of the trouble, and tries to convince Marnie to halt their relationship, but Marnie in turn suspects Flanagan. They eventually discover that Flanagan is the Knight in question; he was told prior to the students' arrival that he was the last of the Order.
Edgar Dalloway, head of the Witches' Council and father of one of the students, is the real root of their problems. He wants to keep Halloweentown isolated from the mortal world, and used Flanagan to ensure the failure of Marnie's project. This, he hoped, would cause a negative reaction in Halloweentown and keep the portal between Halloweentown and the mortal world closed.
The Halloweentown students use the school's Halloween carnival to improve mortal attitudes toward magical folk. Their haunted house depicts the ordinary lives of creatures that have typically been seen as monsters in the mortal world, including displays like the "Monster Tea Party" and ogres "picnicking in their natural setting", and winds up boring the carnival goers. Gwen meanwhile uses a witch's glass to hunt down the missing student whom Dalloway imprisons.
At the school Halloween carnival, Edgar Dalloway launches magical attacks against mortal students by bringing the inanimate monsters in the haunted house to life. The ensuing damage and panic spiral beyond Marnie's and Aggie's ability to contain them, including a reanimated skeleton which grows 30 feet tall. Flanagan incites a mob to corner the Halloweentown students. Cody shames the crowd, the students reveal themselves, and the crowd accepts them for who they are. Flanagan also renounces being a knight and accepts Aggie.
Dalloway claims the Cromwell magic, but Gwen, accepting her magic abilities, has shown the evening's events to the full Witches' Council. They return the Cromwell magic, Gwen returns with the student whom Dalloway had imprisoned, and the Council imprisons Dalloway in another witches glass. (At this point the series diverges from real history quite dramatically, with the existence of Halloweentown and its inhabitants becoming known to the population of Earth).
The portal between Halloweentown and the mortal world opens in the middle of the haunted house, and crowds of kids from Halloweentown cross over to enjoy the carnival together with mortal world kids. Marnie flies off for a romantic broom ride with Cody and, while flying over the carnival, they kiss.
- In the movie there is a serious personality change in Gwen: in the first two movies, she does not like to use her magic, but in Halloweentown High she accepts magic.
- Sophie appears only four times in the movie and does not use any magic. Because the actress is older, it makes it hard for some viewers to realize she's portraying Sophie, who was younger in appearance during the previous movie.
- In Halloweentown II: Kalabar's Revenge, the family moved into a new house, and they appear in this film to have moved again, meaning that they have been in a different house in every movie except for the fourth one as they are still living in the same house from this movie.
- Lucas Grabeel and Olesya Rulin also appeared together in the High School Musical trilogy.
- The highschool scenes, shot mostly at Juan Diego High School in Salt Lake City, Utah had to be carefully staged. This private Catholic High School is, understandably, full of Christian artwork and statues, requiring hallway scenes to be full of wall "posters" to cover any religious prints or careful camera angles to avoid any religious statues in the alcoves.
- Kimberly J. Brown - Marnie Piper
- Debbie Reynolds - Splendora Agatha "Aggie" Cromwell
- Joey Zimmerman - Dylan Piper
- Emily Roeske - Sophie Piper
- Judith Hoag - Gwen Piper
- Lucas Grabeel - Ethan Dalloway
- Michael Flynn - Edgar Dalloway
- Finn Wittrock - Cody
- Eliana Reyes - Cassie
- Clifton Davis - Phil Flanagan
- Todd Michael Schwartzman - Pete the Werewolf
- Jessie Harward - Chester the Ogre
- Clayton Taylor - Chester's Human Disguise
- Olesya Rulin - Natalie the Pink Troll
- Jeff Olson - Six Armed Council Member
- Frank Gerrish - Pumpkinhead Council Member
- Mowava Pryor - Vampire Council Member
- Aaron Justesen - Mummy Council Member
- Frank Welker - Special Vocal Effects