In "The Hound of the Baskervilles," Arthur Conan Doyle explores themes of fear and uncertainty, particularly through the character of Sherlock Holmes and the mysterious events surrounding the Baskerville estate. The quote, "It seems to leave the darkness rather blacker than before," suggests that the more one uncovers the truth, the more ominous the reality can seem. This encapsulates the essence of the novel, where each revelation intensifies the sense of dread rather than diminishing it.

The darkness referred to in the quote symbolizes the pervasive evil and mystery enveloping the characters, making the atmosphere increasingly tense. As Holmes investigates the supernatural legend of the hound, his efforts sometimes illuminate the shadows, yet often they reveal deeper and more unsettling fears. Thus, the quote reflects the paradox of enlightenment in a world steeped in horror, underscoring the complex interplay between knowledge and anxiety in the narrative.