Horror wears many masques, but often it comes down to messing with people's religious underpinnings. People's safe ideas of what their religion means to them, what it has to say about humanity, and how they find comfort in it and its words and rituals. But then novels and movies like "The Exorcist" and "The Omen" come along, scaring us with religion that's no longer comforting. Whether it be Satan himself, speaking through a little girl, or the devil's son growing up almost normal except for the Evil One's influence, these works take what used to be comforting and spin it back to its roots, really, where people truly feared the deities they worshiped. Or to put it another way, religion can itself be as frightening as it is usually comforting. The mysterious rituals, the hinted-at cosmic power, the fear instilled in believers and nonbelievers alike. Vengeful gods, demons, angels, and supernatural underlings from a dozen traditions. The stew can be a potent one, if spiced correctly and stirred with panache.

Tom Piccirilli stirs this heady stew and serves it up steaming in super-size portions. Think of "A Lower Deep" as a romp through Revelation, in which Piccirilli creates a sort of Biblical surrealism blending elements and images of the occult with those of Judeo-Christian tradition. The cover only hints at the operatic sprawl of horrors within.

On the surface a strange and warped quest, the nameless Necromancer and his wise-ass familiar, Self, return to the place where Nameless parted ways with his old nemesis, Jebediah, after the death of his one true love. Jebediah also murdered the rest of his coven in a bid for power, and now he needs Nameless to use his abilities to bring the coven members back to life. Jebediah's goal is to bring about the second coming of Christ and, incidentally, Armageddon. Nameless and Self teeter on the edge of good and evil, facing a host of creatures out of every religious tradition. Indeed, they themselves seem alternately Christlike and demonic, their true nature always kept to a blur.

Witchcraft and Christianity collide in this unique tale, disparate elements intertwining—blessed and blasphemous, holy and unholy, sacred and sacrilegious, good and evil (god and devil). Duality rounds out the list of themes, best exemplified by the characters' familiars, all of whom reflect their masters like fun house mirrors. Grotesque images of twisted virgin births slither and slime their way into your psyche, rolling around with the "pure" images we all grew up with and tainting them into delicious sacrilege.

The fact that the tale refused to lead where I thought it would is testament to Piccirilli's care in crafting a sequence of terrors that is also a mystery, for one is unlikely to foresee the exact nature of the apocalyptic ending. And Necromancer's true self (not Self) remained a mystery to me, though it hovered at the tip of my brain to mock my lack of perception. I like when things elude me and make me work harder.

Occasionally just slightly flawed by an almost frenetic intensity, "A Lower Deep" is nevertheless one of the most ambitious and effective Biblical thrillers ever attempted, in no way harmed by comparisons to Blatty. Piccirilli's Necromancer, star of various short stories, takes center stage (along with Self, who provides a sort of comic commentary to the proceedings) decisively from the beginning, where he battles demons in the hinterlands of America, to an ending which plays out in an amazingly topical snapshot of current news-footage Jerusalem. Reading this novel, one can't help but wonder whether the apocalypse is indeed on the way, and if those dark clouds massing on the horizon aren't actually swarms of breast-plated locusts. It's that chilling.