Set in the year 1844, the game stars the man-beast Cornell in his quest to prevent his adoptive sister, Ada, from being used as a sacrifice to resurrect Dracula. The game opens as Cornell arrives at his village, which has been burned to the ground by Dracula's minions. He finds Ada's pendant in a doorway and follows her scent to Dracula's castle.
During the course of the game, Cornell comes upon a grand estate owned by the Oldrey family: J.A. Oldrey, the master of the Villa, Mary, his wife, and Henry, their son. Gilles de Rais and Actrise have turned Oldrey Senior into a vampire. At Mary's request, Cornell guides Henry to safety. Later in life, Henry returns to Castlevania to save kidnapped children.