Castleween is an action-adventure game for PlayStation 2 in which players control siblings Alicia and Greg as they seek to rescue their friends who have been turned to stone by a bogeyman. Set on Halloween, the duo navigates through a series of eerie environments, including cemeteries and haunted houses. Players must alternate between the characters, utilizing magic learned from allies to overcome obstacles and ultimately confront the Mad Scientist to save their friends.
Alicia and Greg set off with their friends one Halloween night to look for a house in the forest where they could stock up on goodies. Upon reaching the house, Greg and Alicia's friends are turned into stone by a bogeyman. To save their friends, the two heroes must enter the world of the dead. In order to find their friends and set them free, they need to make it through cemeteries, haunted houses and sinister laboratories. Only one person at a time is allowed to enter the world of the dead, so Alicia and Greg must take turns in order to make their way through the danger that awaits them. Friends like the Goblin and Jack O'Lantern will teach them magic tricks that will help them to overcome obstacles along the way. They must find the Mad Scientist's laboratory to get their friends home safe and sound.