Favourite classic book.
I have to admit I really haven’t read many classics, I have many on my shelves but none have been read yet. But I think I would say I Am Legend by Richard Matheson is one of my favourites though I’m not sure if it is even considered a classic.
Matheson goes to great lengths to rationalise the vampire myth, transplanting the monster from the realms of folklore and Victorian supernaturalism to medical inquiry and rational causation. Though the assailants are described as “vampires”, and their condition is transmitted through blood there is little similarity between them and traditional vampires from gothic novels.
However I Am Legend was massively influential in the development of the zombie genre and popularised the concept of a worldwide zombie apocalypse due to disease. Although that idea has now become commonplace, a scientific origin for zombies was fairly original when written. And that makes it a classic to me.