Heh, heh, heh. Something nasty is about to happen. That unsuspecting motorist has just noticed a warning sign: CAREFUL! CHILDREN AT PLAY. But he has failed to spot the two pop-eyed, toad-shaped little boys who stand gleefully poised to tip an enormous boulder down on top of his nice shiny car.

In real life, of course, only maniacs would laugh. But when Charles Addams served up the moment in one of his deliciously grisly cartoons, thousands of otherwise sane human beings yelped with uncorseted delight. Now why on earth is that? Probably it's because we all have a fiend or two tied up in the emotional basement. Probably we laugh because we see our own carefully hidden ghouls in Addams' monsters and feel a glorious relief when our terrible secrets abruptly erupt into the light—and turn out not to be so terrible after all. That is the heart of Addams' appeal, the reason millions treasure his cartoons as personal epiphanies. In an age of anxiety, he caught us unawares, helped us befriend our worst fears and offered us the absolution of innocent laughter.

When Charles Addams died on Sept. 29 at 76, the world lost a rare and elegant spirit. Other entertainers have found humor in horror, but only Addams expressed it with the pure, contagious excitement of a naughty boy who has just dropped a worm in his sister's sarsaparilla. He was wicked without meanness, sardonic and affectionate at the same time. He loved those scarifying creatures that dwelt in his imagination, and he made us love them too. For more than five decades he played ghoul-tender on the New Yorker team, and his cartoons were the magazine's most talked-about feature. Thirteen collections of his drawings were published. Eventually Charles Addams characters infested the doll market, and a goofy/ghastly sitcom called The Addams Family ran for two years on ABC and then made the rounds in syndication. He became history's most popular cartoonist, lord of his own genre, and his boulders of evil gathered large wads of lucre as they rumbled through the night mind of an affluent society.

Dozens of Addams drawings are classics. "Congratulations," a nurse announces to a hideous male in a hospital waiting room. "It's a baby." "George! George! Drop the keys!" screams a frantic spouse as she races along a beach beneath her husband, who is being carried off in the claws of a giant bird. "Oh, I like missionary all right," a dyspeptic cannibal sadly tells his dinner partner, "but missionary doesn't like me." As an actress stares in horror from a screen at something out there in front of her, the movie audience has turned and is staring in horror at—US!

Addams' pop masterpiece is the fiendish Addams family. What darling little demons they are. There's wife Morticia, thin and cold as a carving knife, who wears a slinky black gown and knits four-legged baby garments. There's husband Gomez, a boorlesque of Thomas E. Dewey, looking like a pig with a mustache. Uncle Fester resembles what might be left of Peter Lorre after a brisk acid bath. Lurch the butler is a Frankenstein monster who has popped his rivets and left his brains in formaldehyde. Wednesday, the dear daughter, is a limp strip of linguini with an octopoid head and a terminal whine ("Mom, can I have the broom tonight?") And Pubert, that poisonous spider of a lad, keeps a Komodo dragon as his personal pet and lights a roaring blaze to welcome St. Nick when he drops down the chimney on Christmas Eve.

What sort of creature could perpetrate these perversities? Not at all the sort you'd expect. Tall, well-muscled, crinkly-eyed and yam-nosed, Addams was a charming, level-headed gentleman who looked like a double exposure of Walter Matthau and Lyndon Johnson and delighted colleagues with his dry, quiet wit. "He was good to be around," says one, "because he was comfortable in his own skin." He was born that way, friends say. He grew up in a well-to-do New Jersey family, studied at Colgate and the University of Pennsylvania, then went on to art school in Manhattan. In 1932 he sold his first drawing to the New Yorker for $7.50, and by 1935 he was on contract.

Addams did his work with insidious skill. At first glance, his drawings seem crude, but art critic John Russell has noted "the rock-solid composition, the eye for scale and placement, the calculated ordinariness that lures us into the trap." Cartoonists admire Addams' sense of architecture. "You could build the rooms he draws," says his friend Frank Modell, "and his figures are constructed like Romanesque temples." James Stevenson, another friend, finds his buildings "weirdly animated. You're not sure what's alive in his drawings and what isn't." And all these effects, Modell says, were achieved with technical mastery. "When Chas painted a cartoon, he began at the top and worked straight down to the bottom—like a rug weaver."

As his legend grew, Addams quietly and shrewdly promoted it. He crammed his Manhattan flat with sinister bric-a-brac—crossbows, biopsy scissors, an executioner's ax, an embalmer's rack that served as a coffee table—and put stained-glass windows in his van. Fame and charm won him early " entree to cafe society, where he indulged his passions for classic cars (among them a bright blue 1926 Bugatti) and classy ladies (among them Joan Fontaine, Jackie Onassis and even Greta Garbo). Now and then he got married. His first wife, Barbara Day, a raven-haired beauty who eerily resembled Morticia, divorced him in 1951 and later married author John Hersey. Second wife Barbara Barb said goodbye in 1956 and became the bride of a British lord. But Addams' third marriage, to a spirited widow named Marilyn, was made in—wherever—from the start. The bride wore black, and the ceremony was held in a pet cemetery. The relationship, Addams said, was civilized. "I live in New York City. My wife lives in the country. We see each other only on weekends. It's great."

In recent years Addams' once robust health began to falter. "I'm feeling a little frail," he confessed on the morning of the day he died. Nonetheless, he jumped in his new Audi and went blasting off to Connecticut—as usual at 80 mph or better—with Modell as a passenger. After five hours' hard driving, he took a snooze at Frank's place, chatted for a time with Modell and Stevenson and then went blazing back to New York. His heart gave out as he parked outside his Manhattan apartment house. "He's always been a car buff," his widow said philosophically, "so it was a nice way to go."

For admirers there is other consolation. The New Yorker has four unused Addams cover drawings and a dozen new cartoons. In those and the books of his wonderful, wayward world, Charles Addams will keep coming back to haunt us, and free us, and let us laugh.