Our Lady of Darkness by Fritz Leiber (1977): The last of the prolific and long-lived Leiber's truly great horror-dark-fantasy novels, and for my money the best, Our Lady of Darkness plays with themes and concepts Leiber first explored nearly 40 years earlier in his seminal horror story "Smoke Ghost" (1940).
In that dark and terrific story, we discover that the multiplying and expanding urban landscapes of the 20th century breed their own peculiar types of ghosts, spirits, and perhaps even gods. In Our Lady of Darkness, we begin to learn just what sorts of entities may haunt the 20th century, and why, and to what ends. The list of writers who owe a debt to Leiber's concept includes such luminaries as Neil Gaiman, Joe R. Lansdale, Ramsey Campbell, and a veritable plethora of others.
Leiber's semi-autobiographical stand-in of a protagonist, writer Franz Westen, is a recovering alcoholic who lives in a somewhat odd, old apartment building in San Francisco in the late 1970's. Two books he purchased while in a near-blackout state several years earlier begin to occupy his mind: a bizarre Depression-era screed about the supernatural dangers posed by the existence of cities, and an unsigned journal from the same time period which Westen comes to believe belonged to (real) horror writer Clark Ashton Smith.
Smith pretty much permanently moved to the country in the late 1930's, avoiding cities thereafter. Why? What did his brief friendship with the writer of the screed reveal? Looking out across San Francisco with his binoculars to the top of Corona Heights, a wooded hill in the middle of developed urban space, Westen sees a strange, brown figure capering and dancing -- and then taking notice of his attention.
And we're off. Leiber blends the real and the fictional into a fascinating mix of horror, dark comedy, and supernatural speculation. Jammed with enough material for a novel ten times its modest length, Our Lady of Darkness remains light on its feet throughout. Spiked with fine and occasionally shocking moments of horror, the novel nevertheless presents a protagonist who never stops trying to think his way through the bizarre events he's been dropped into because of these two books of (seemingly) accidental purchase.
Westen's friends in the hotel are also well-drawn, as is the libertine expert on the supernatural whom Westen turns to for information on San Francisco's occult past. Real-world figures that include H.P. Lovecraft, Jack London, and Ambrose Bierce are woven plausibly into the story, their fictions and their lives making the events of the novel seem more plausible in a completely loopy way with each passing page. Leiber's fictional occult speculations become more convincing than most of our world's real occult writings.
Leiber was one of the 20th century's most gifted cross-genre writers. He helped create the sword-and-sorcery genre with his wry and long-running Fafhrd and the Grey Mouser series, wrote piercingly good science fiction with his The Big Time, "A Pail of Air," and "Coming Attraction" (to name just three), and helped modernize horror in a way that still hasn't completely taken hold, as the current proliferation of all those tired vampires and werewolves continues to show.
His theatrical background informed works that include "Four Ghosts in Hamlet," while his life-long fascination with chess gave us one of the two or three finest chess-horror pieces ever written, "Midnight by the Morphy Watch." That he could also do pitch-perfect homages to his old pen-pal H.P. Lovecraft or move seemingly effortlessly into post-modern strangeness while already in his 50's with stories that include "The Winter Flies" and "Gonna Roll the Bones" seems almost unfair to other writers. Our Lady of Darkness may be his finest novel -- in any case, it's one of no more than twenty or so of the finest novels ever gifted to the horror genre to call its own. Highly recommended.