Halloween is a 3D platform game with third person views in the world of haunted houses and graveyards. The player will control two characters: Ann, a little girl, who is disguised as a witch; and Greg, a little boy, who is disguised as a devil. "To make best use of their complimentary capacities, the player will have to switch from one character to the other." In this manner, the player will be able to overcome the difficult points of the game and reach a successful conclusion.

"This game will be based on the world famous Halloween traditional night and the very latest Kalisto Entertainment platform adventure engine. Halloween plunges the entire family, kids and parents, into a terrifying world of a haunted house, a cemetery, a disused film studio, and a forgotten pyramid. Gosh, who could ask for more. The sources of inspiration for this game are Medieval I & II, the novels of Stephen King, and horror films such as, Amityville, The Fog, and The Mummy."

"You are in Hollow City, USA and you are playing on Halloween night. Four children, Morgane, Vladimir, Satanas, and Gaspard [In the USA? I like the names but they are a trifle unusual for this country] are out playing trick or treat on their neighbors." They are dressed as a ghost, a witch, a vampire, and a devil. They approach a large house on the edge of town. It looks empty, but there are two grinning pumpkins near the front door, shining in the dark. The children hesitate but finally decide to enter the house. Big mistake? Evil spirits have been drawn to the house by the dark of the night and by the lure of Halloween. They want to play among the living. The children are trapped in the house, and every time they attempt to escape, they are drawn deeper and deeper into the mystery.