The allure of 'dark corners novel mystery books' lies in multiple factors. First, the element of surprise. These books are full of unexpected twists and turns, like in 'In the Woods' where the truth about the past is not what it seems at first. Second, the atmosphere. The dark and often foreboding settings create a sense of unease and excitement. And finally, the exploration of complex relationships. Characters in these books are often involved in intricate webs of relationships that are part of the mystery, such as in 'The Secret History' where the relationships between the students are key to understanding the murder mystery.