Kelaster is a horror story about how three students become trapped in a college dormitory after the Movement Control Order (MCO) is enforced. Two male students, Usop and Zul, are forced to accompany Ain, who is alone and forced to seek help in the male dormitory. Strange tragedies begin to occur when they try to get help for Ain. The situation becomes more complicated after Usop and Zul share stories about ghost disturbances and supernatural beings they have experienced. When it's Ain's turn to share her experience, Ain suddenly disappears. Usop and Zul immediately search for Ain, and when they find her, Ain is inside a bus near their college. There, all the mysteries and secrets of the disturbances they all experienced are revealed.