Set in 1839, the player takes on the role of Daniel, a young man from London who awakens in the dark halls of Prussian Brennenburg Castle with little memory of himself or his past. He remembers only his name, that he lives in Mayfair, and that something is hunting him.

Soon after waking, Daniel finds a note he wrote to himself. It explains that he deliberately erased his memories because he could not bear losing his innocence.

The note tells him to descend into the castle’s Inner Sanctum and murder Alexander, the castle’s baron. It also warns that a “living nightmare” is chasing him, and that he can only escape it for as long as possible because there is no way to fight back.