Finn Belli is an 18-year-old boy who recently moved to college. While visiting his parents, he is involved in a car accident, and awakens in a cage in the dungeon of a castle. His memories of the incident are hazy. Noting that the cage that keeps him prisoner has been left unlocked, he steps out and begins searching for answers and a way out of the castle. Soon after, he befriends a White Shepherd named Hewie. As Finn begins to unravel the mystery in which he finds himself, he learns that he is the carrier of the Azoth, an alchemic element, which for unknown reasons is being sought by Riccardo, the castle's keeper.
The first enemy Finn encounters is Debilitas, a large, mentally disabled groundskeeper who thinks of Finn as one of his dolls. Finn learns from a mysterious man named Lorenzo that to escape the castle, he needs a staff from the chapel. However, upon taking the staff, Debilitas corners Finn and Hewie, forcing a confrontation. They defeat Debilitas, but soon find their next enemy, Daniella, an icy maid. Daniella covets Finn's ability to smell, taste, touch, feel, and "experience pleasure." She is especially jealous that Finn can create life. Daniella is defeated when she is impaled with a shard from a ceiling window pane.
The third villain is Riccardo, who wields a flintlock pistol. For the majority of the game, Riccardo keeps his face hidden under a hood. Upon revealing himself however, Finn is shocked to see his dead father's face. Riccardo reveals that he and Finn’s father, Ugo, are clones. He murdered Ugo in the car accident as revenge for leaving the castle and marrying Finn's mother. He plans to use Finn, by means of his Azoth, to bring about his own rebirth, so that he may live forever. As they fight atop a water tower, Hewie rescues Finn by attacking Riccardo, causing him to fall from the summit.
The final enemy is Lorenzo, who seemed to be an ally, but who now menaces Finn in several different forms. Finn first meets him as an old, crippled man. He tells Finn that Riccardo was always the problem child, and that he created both Riccardo and Ugo in an attempt to find a body with an Azoth which he could use to gain immortality. Ugo had the Azoth, but left the castle to marry Ayla. Now with Riccardo dead, Lorenzo believes that Finn is his, so he can take the Azoth he inherited from his father. He chases after Finn, but he is able to crush him in a rock press. However, he soon encounters a resurrected, youthful Lorenzo; the life energy he acquired from Riccardo's body has allowed him mastery over his own aging process. With the help of Hewie, Finn causes Lorenzo to fall into a pit of lava. At this point, the castle begins to shake and collapse, and Lorenzo returns as a flaming skeleton. He chases Finn as he heads for the exit, and attempts to block his escape, but as they reach the door, he finally dies, and Finn and Hewie leave the castle.