Author: H.P. Lovecraft
Genre: Short story collection
Edgar Allan Poe receives the majority of the horror genre's "most influential writer" praise, and Stephen King is our modern-day titan of fear, but H.P. Lovecraft is undoubtedly just as crucial, if not more so, than those other guys.
Back in the 1920s and '30s, the reclusive, eccentric Rhode Island native wrote wildly imaginative short stories bathed in his command of atmospheric terror, invention of the Necronomicon (a fictional book of the dead), and the game-changing Cthulhu Mythos, that of universe dominated by cosmic monsters and supernatural gods.
All of that, plus several weird tales that don't necessarily fit into those parameters, can be found in this exhaustive collection of Lovecraft's renown classics and overlooked gems.
Fun Fact: Lovecraft shared close, letter-form, frequently exercised correspondences with authors Robert Bloch (Psycho) and Robert E. Howard (the Conan the Barbarian series).