As Halloweentown prepares to celebrate its 1,000th anniversary, Marnie Piper and her brother Dylan return to Witch University, where trouble is in session from the Sinister Sisters and from someone who's plotting to use Marnie's powers for evil.
| Actor | Role |
|---|---|
 Sara PaxtonMarnie Piper | Marnie Piper |
 Judith HoagGwen Piper | Gwen Piper |
 Lucas GrabeelEthan | Ethan |
 Joey ZimmermanDylan Piper | Dylan Piper |
 Kristy WuScarlett | Scarlett |
 Keone YoungSilas Sinister | Silas Sinister |
 Millicent MartinProfessor Periwinkle | Professor Periwinkle |
 Summer BishilAneesa | Aneesa |
 Leslie WingDr. Goodwyn | Dr. Goodwyn |
 Debbie ReynoldsAggie Cromwell | Aggie Cromwell |
| SScott StevensenDr. Grogg | Dr. Grogg |
 Katie CockrellSage | Sage |
 Kellie CockrellSaphire | Saphire |
 Christopher Robin MillerYoung Troll | Young Troll |
 Micaela NelliganWrinkled Old Witch | Wrinkled Old Witch |
 Brighton HertfordYoung Periwinkle | Young Periwinkle |
 Stefania BarrBratty Daughter | Bratty Daughter |
| EEliza WrenGeek Girl | Geek Girl |
 Steve LunaJock | Jock |
 Darren EwingMorose Cashier | Morose Cashier |
| SSteve AndruzziSnooty Buyer | Snooty Buyer |
| JJanice PetersonTimid Mom | Timid Mom |
| CChevy Lamont CofieldStudent (uncredited) | Student (uncredited) |
| CCheyenne HallVampire (uncredited) | Vampire (uncredited) |
 Tisha VaculinCheerleader #1 (uncredited) | Cheerleader #1 (uncredited) |