Thomas Ligotti says, “I tend to stipulate in my work that the world by its nature already exists in a state of doom rather than being in the process of doom.” Courtesy Chris Mars / Chris Mars Publishing

The TV show “The Walking Dead” is one long exercise in tension. But the zombies—the supposed centerpiece of the show’s horror—are not particularly frightening. Gross, to be sure, but also knowable, literal. You can see them coming from yards away. They are the product of science gone wrong, or of a virus, or of some other phenomenal cause. They can be destroyed with an arrow through the brain. More aberration than genuine monsters, they lack the essential quality to truly terrify: an aspect of the unreal.

The horror writer Thomas Ligotti believes that even tales of virus-created zombies—and other essentially comprehensible creatures—can elicit what we might call, quoting the theologian Rudolf Otto, “the wholly other,” but it requires a deft hand. The best such stories “approach the realm of the supernatural,” he told me over e-mail, even if their monsters are entirely earthly. As an example, he pointed to “The Texas Chainsaw Massacre,” “wherein the brutality displayed is so deviant and strange it takes off into the uncanny.” Ligotti doesn’t require bloodthirsty villains to convey a sense of impending horror, though. “I tend to stipulate in my work that the world by its nature already exists in a state of doom rather than being in the process of doom.”

Ligotti’s stories, which have been reissued in a new Penguin Classics volume that brings together the books “Songs of a Dead Dreamer” and “Grimscribe,” are fugues of the creeping unknown. They often begin with a moment of banality: a visit to a new town, an academic’s research project, the tearing down of an old building. His narrators are fairly nondescript, if occasionally a tad morose. But they are all sensitive to or attracted by a slight bend in reality. Something leaks through into the known world, and the protagonist, often already on the edge of sanity, is doomed by the encounter with whatever it is—say, the spectre of a demolished house that seems to exist in a liminal place between wintry nights and the realm of the dead.

Whether or not this visitation “actually” happens is irrelevant for Ligotti; it’s the psychological dissolution of his characters that he’s interested in. And because Ligotti reveals so little, we are left to conjure our own twisted imaginings. The things that go unsaid are more terrifying than zombies chewing on arms and legs. In this way, Ligotti owes more to “The Turn of the Screw” than to H. P. Lovecraft, though it’s the latter with whom he is most often associated, as he has become grouped in with the subgenre known as “weird fiction.” Lovecraft is its patron saint.

While Lovecraft had his Cthulhu Mythos, a collection of places and deities that have been reimagined by writers from Robert E. Howard to Stephen King, there is no “Ligottian mythos,” nor does Ligotti explicitly play in Lovecraft’s world. But there are names and settings that appear in many of his stories, all of which seem to take place in the same world—towns where “steeply roofed houses had been erected on a sudden incline, their peaks appearing at an extraordinary elevation above the lower building,” rooms that “border on the voids of astronomy” populated by nameless, dark-hooded cultists. Ligotti calls this his “fictional geography,” and explains that his stories exist in “enclosed environments” that have more in common with dreamscapes than any real-life locations. “They may seem as if they belong in the world,” he told me, “but are just at its margins.”

In “Dr. Locrian’s Asylum,” the head of a hospital for the mentally ill has perfected a means of unlocking the insanity of his patients through a “battery of hellish ordeals,” not in an effort to cure them but to teach them that their madness is a gnostic state of being that reveals the true horror of existence. “The Sect of the Idiot” follows a man as he discovers a cult of people who have willingly become grotesque versions of their former selves, staring forever into the void with their “withered, wilted claws bearing numerous talons that tapered off into drooping tentacles.” “The Journal of J. P. Drapeau,” more pastiche than story, reveals the inner life of an artist who is “unsustained by any habits of the human,” and whose diary describes explicitly what many of Ligotti’s other narrators only allude to, such as the “two tiny corpses, one male and the other female” that “rattle around the enormous closet” in his room.

The stories in the Penguin anthology previously appeared in collections put out by Subterranean Press, a small publisher of specialty fantasy, science fiction, and horror. Last year, Ligotti was name checked repeatedly by Nic Pizzolatto, the writer of HBO’s “True Detective,” and his work began to reach a much wider audience. The show’s breakout character was Rust Cohle, played by Matthew McConaughey; in lengthy monologues, Cohle presented a world view straight out of Ligotti’s stories. (After the season ended, one Ligotti fan even accused Pizzolatto of plagiarism.) But Cohle was redeemed by the end of his run on the series. Ligotti’s characters are never redeemed.

“Whether or not there is anything called the divine is neither here nor there,” Ligotti told me. “It’s irrelevant to our sense of what is beyond the veil.” Ligotti believes that fiction can put us in touch with that sense of things unseen, that it can create an encounter with—to quote Rudolf Otto again—the mysterium tremendum et fascinans, a state that combines terror and enchantment with the divine. In fact, Ligotti believes that “any so-called serious work of literature that doesn’t to some extent serve this function has failed.” It’s not a matter of genre, he says. He cites Raymond Chandler’s Philip Marlowe as a character who would go wherever the clues took him, no matter how deep into the heart of the “unknown.” “Chandler wanted his detective stories to invoke the sense of the ‘country behind the hill.’ ”

Because Ligotti has no interest in whether or not that world beyond actually exists, there is a tension, an unanswered question, in his work: Can we locate the source of this horror? His characters are often confronted by people or groups who worship something so alien that their rituals don’t conform to any identifiable modes of religious practice. Usually, they involve some form of sacrifice or other suggestion of violence. The implication seems to be that, even if there is meaning in the universe, that meaning is so foreign, so strange, that we could never understand it, and it could never make a difference in our lives. Any attempt to penetrate it will only lead to madness.

As a practical matter, Ligotti believes that the short story is the most potent means for conveying this idea. “A novel can’t consistently project what Poe called a ‘single effect,’ ” he explains. “It would be too wearing on the reader—too repetitious and dense, as would, for instance, a lengthy narrative poem written in the style of a lyric poem. A large part of supernatural novels must therefore be concerned with the mundane and not with a sense of what I’ll call ‘the invisible.’ ”

Trying to get Ligotti to explain what he means by the “invisible” is not easy. “I’m not able to see my stories as establishing or presuming the existence of a veil beyond which the characters in them are incapable of seeing. I simply don’t view them in this way. ” But his characters, I insisted, suggest that we are all capable of seeing beyond the veil, though it’s impossible to tell if they are simply mad, or if they have indeed perceived something outside normal perception. I asked Ligotti if he saw a difference between these two states of consciousness. “The only interest I’ve taken in psychological aberrancy in fiction,” he answered, “has been as a vehicle of perceiving the derangement of creation.”