In this film publicity image released by Warner Bros. Pictures, Ralph Fiennes portrays Lord Voldemort in a scene from "Harry Potter and the Deathly Hallows: Part 2." (Anonymous/AP)

Who isn’t a villain at one time or another? In some countries, authors are villains. In Washington, a person of an opposing political view can only be a villain. In the world of literature, witches, bullies, an oil magnate, a hungry shark and even the bitter cold are terrifying. And of course there’s that reliable rascal, Satan himself, in all his many forms. But what about the Red Baron, that fiend who annoys the World War I flying ace Snoopy in the skies over “Peanuts” — is he the ugliest demon ever to flow from an author’s or an artist’s pen? If you believe that, then you also believe that villains truly do come in all guises, which is exactly what makes them so exciting. We asked these National Book Festival authors to nominate the most terrible villains who have ever haunted a writer’s imagination.

The worst of all, of course, is the witch in “Grimm’s Fairy Tales,” who locked Hansel and Gretel in a cage to fatten them for the kill. A crone who eats children — how can you beat that? — Marie Arana

I asked my 19-year-old son what he thought: He suggested the implacable cold in Jack London’s “To Build a Fire,” which freezes spit in mid-air with an “explosive crackle.” That sounds right to me. — Nicholson Baker

Satan rouses his rebel angels from the fiery pool in an illustration from Book I of the 1688 first illustrated edition of John Milton's 'Paradise Lost'. Engraved by Michael Burgher. (Hulton Archive/Getty Images)

Voldemort in J.K. Rowling’s Harry Potter series. What makes him so creepy is that he and Harry are connected. The idea that we all have some evil in us, or the potential for evil, is a little scary. — Kathryn Erskine

Screwtape from “The Screwtape Letters” by C.S. Lewis. Screwtape, a devil, is no horned and clawed, eviscerating baddie. Instead, he luxuriates like a refined gentleman — one so savvy about human nature that he breezily shepherds souls to ghoulish consumption in hell on nothing more than our mundane vanity, fear and laziness. — Jonathan Hennessey

The Red Baron, Snoopy’s arch-nemesis, is the greatest villain of all time. He engages in dogfights with our beloved beagle, Flying Ace Snoopy, who pilots his Sopwith Camel doghouse. Most mysteriously, we never get to see what the Red Baron looks like. But we know what we would say if we ever ran into him: “Curse you, Red Baron!” — Jennifer L. Holm and Matthew Holm

The Grand High Witch from Roald Dahl’s “The Witches is perfectly terrifying. Gruesome, twisted, creatively cruel and preying specifically on children, this character is about as villainous as they come, and put me completely off whatever little incentive I had to talk to old ladies when I was a child, without first checking, from a distance, whether they were wearing pointy shoes or wigs. — Oliver Jeffers

Kurtz from Conrad’s “Heart of Darkness.” There are few, if any, novels where the character exists and has an ambience in the way Kurtz does, all without making an appearance. Written at a time when most people thought colonizers were sturdy chaps, Kurtz is a figure of surpassing, satanic, credible and bone-chilling evil. And unlike villains in other books, he does not stand at a polar remove from the reader. The reader sees a version of himself in that dark mirror. There’s nothing scarier than that. — Thomas Keneally

Bugs Meany in the “Encyclopedia Brown”series, by Donald J. Sobol. Nobody likes a bully or a cheat. Bugs was the be-all, end-all of kid bullydom, who attempted to thwart Leroy Brown as he solved mysteries for 25 cents plus expenses. Tolkien’s Sauron may have been an all-seeing eye of evil, but Bugs was the in-your-face, inescapable buzz-kill of the coolest 10-year-old detective ever in print. — Denise Kiernan

Goldfinger, because in the universe of impossible supervillain schemes, his was somewhat plausible. Amass a huge fortune in gold, detonate an atomic bomb in Fort Knox, irradiate the U.S. gold reserves and therefore see the value of yours increase a hundred times. Brilliant. — D.J. MacHale

The shark in Peter Benchley’s “Jaws.” No villain ever generated more real-life fear among readers (and moviegoers) or caused such real-world environmental damage. Following the publication of the novel, the number of sharks killed by people began to rise, and has been rising ever since. Benchley himself admitted that his malignant force of nature was one of the reasons for that. — William Martin

That idiot from “The Giving Tree.” What’s he do but take, take, take? And he never learns. I hate that kid. — Brad Meltzer

Norm Oglesby, the millionaire oil magnate and owner of the Dallas Cowboys, in Ben Fountain’s novel, “Billy Lynn’s Long Halftime Walk,” is a loathsome, cosmetically enhanced, bullying lout, shimmering “with high-wattage celebrity,” a “knocked-wonky smile” and the “paralytic force field of his mesmerizing narcissism.” Norm oozes with cheerleader delight as he finds new ways to profit from the spectacle of American boys sacrificing bodies and souls on playing fields at home and battlefields overseas. — David Nasaw

Satan in Milton’s “Paradise Lost is the most erudite, charismatic villain ever. This is our biggest human weakness: how sexy we can find evil and oh, how dangerous that is. Every time I see a declaiming politician, all I can think of is Milton’s Satan, still wooing us 400 years later. — Patrick Ness

Mrs. Danvers in Daphne du Maurier’s “Rebeccais the basilisk-eyed queen of all villains. She is a bad seed blossomed into belladonna in the eerie forcing house of a Cornish castle, and marches in the grand British tradition of the corrupt servant. — Richard Peck

The judge in Cormac McCarthy’s “Blood Meridian.” He is nearly as wide as he is tall and hairless as a stone. Dark words — nihilistic rants reminiscent of Ahab and Satan — come easily to him. He kills men and women and children. He dances naked, sawing a fiddle. And all through this terrifying novel, this terrifying figure remains amused, one corner of his mouth hiked up in a smile. — Benjamin Percy

It’s no contest. Absolutely terrifying, mind-bending, apparently harmless but planning who knows what dastardly deeds once the lights go out — the old lady whispering “hush” in Margaret Wise Brown’s “Goodnight Moon.” Why is she sitting in that chair? Why is she pretending to knit? Why is she pretending to be an old lady? We can see you! You are a rabbit and you don’t have hands! Who knows why she wants us to hush? — Jon Scieszka

Ravana, the 10-headed villain of the Ramayana, who sets this Indian epic into motion by kidnapping the heroine Sita. Talk about a timeless villain — gigantic effigies of Ravana are still burned all over India to symbolize victory over evil. But his motives are so clear and compelling that, in a postmodern twist, some also worship him as a god. — Manil Suri

British Rear Adm. George Cockburn. Two hundred years ago, he was the most hated man in America, and the most feared. During the War of 1812, the ruthless and swashbuckling Cockburn launched a campaign of terror in the Chesapeake. After the burning of Washington, he proudly posed for a portrait, which depicted the city in flames and the admiral shrouded by black smoke. — Steve Vogel

Surely the preeminent villain in literary history is Satan — and I’m happy to recruit as co-nominators the authors of Genesis and Job. Also, Dante, Milton, and Mickiewicz; and the creators of “Damn Yankees.” For behind every fictional or historical villain is the ur-bad guy, whispering songs of lethal self-absorption in the lesser villain’s ear. — George Weigel