I grew up watching Scooby-Doo, Where Are You! every Saturday morning. The Hanna-Barbera cartoon had launched in 1969, two years after my birth, so it was precisely in my little-kid sweet spot. Much as I loved it, though, the feeble animation and repetitive plots were apparent even to the young me. Whereas characters such as Mickey Mouse and Bugs Bunny seemed eternal, extending far into the past and future, Scooby-Doo felt like a show just for that particular moment, for my specific childhood.

Fast-forward 35 years or so, and to my astonishment, my children loved it just as much as I had. I probably wound up watching more Scooby-Doo episodes with my kids than I had watched as a kid. Evidence suggests that my experience is not unique. Scooby-Doo, believe it or not, has over the years been the subject of at least 19 TV series (on CBS, ABC, the WB, Cartoon Network, and Boomerang); more than 40 animated films; and two live-action movies in the early 2000s, the first of which grossed $275 million worldwide. A new series featuring celebrity-guest voices, Scooby-Doo and Guess Who?, premiered last year. And a new animated movie, Scoob!, starring Zac Efron, Amanda Seyfried, and Tracy Morgan, is scheduled to be released in mid-May.

Which raises the obvious question: What on earth is going on? Why has Scooby-Doo—described by the New York Times film critic A. O. Scott in 2002 as “one of the cheapest, least original products of modern American juvenile culture”—outlasted not only such Hanna-Barbera brethren as The Flintstones and Yogi Bear, but also pretty much everything else on television? The Washington Post’s Hank Stuever once summed up the cartoon’s message as “Kids should meddle, dogs are sweet, life is groovy, and if something scares you, you should confront it.” But that hardly seems enough for half a century of on-air appeal.

The essential premise, for those not weaned on the show, is straightforward. A group of four teenagers—some of whom seem considerably older (more on this in a moment)—and a Great Dane, Scooby-Doo, drive around in a van called the Mystery Machine in search of, yes, mysteries. (The gang, like its later Hanna-Barbera cousin, Josie and the Pussycats, was originally conceived as a band that would play a musical number each episode.)

The mystery they find almost always appears at first to be paranormal—a vindictive ghost or ghoul, a rampaging dinosaur—but is ultimately revealed as an elaborate hoax involving disguises, holograms, hidden wires, phosphorescent paint, or some combination thereof. Each time the gang unmasks the genuine villain, typically male and on the older side, he utters some variation of “And I would’ve gotten away with it if not for you meddling kids.”

The Mystery Inc. members are Fred, the blond, broad-shouldered presumptive leader of the group (who wears, implausibly, an ascot); Daphne, the fashion-conscious redhead and semi-comical damsel in distress (a stereotype that the show subverted in its later iterations); Velma, the frumpishly sweatered and bespectacled brainiac; and Shaggy, the ever-famished slacker-coward defined by his prominent slouch and chin grizzle. Scooby himself—his name was inspired by Frank Sinatra’s “dooby dooby doo” scat in “Strangers in the Night”—is inseparable from Shaggy and in many ways indistinguishable: same appetite, same poltroonery, same plot functions. Essentially split aspects of the same character, the two are not id and superego, but something closer to id and more id. A typical story line involves Daphne getting kidnapped or otherwise endangered; Fred devising a Rube Goldberg–esque, and spectacularly unsuccessful, trap to ensnare the villain; and the case being wrapped up by a blend of Velma’s smarts and Shaggy/Scooby’s bumbling good luck.

The show owed its launch in part to complaints that Saturday-morning cartoons—including Hanna-Barbera’s Space Ghost—were becoming too violent. So the producers William Hanna and Joseph Barbera (along with the story writers Joe Ruby and Ken Spears, and the animator Iwao Takamoto) decided that their new show wouldn’t merely solve mysteries; it would demystify them altogether. As any parent knows, the surest way to comfort kids is to offer them an alternative explanation for the horrors that go bump in the night: It was the cat, or the wind, or the uncle who forgot where the guest room was. In the premiere of Scooby-Doo, “What a Night for a Knight,” the ambulatory suit of armor freaking everyone out is discovered to be Mr. Wickles, the seemingly hapless museum curator who is also (gasp!) a secret art smuggler. Case closed. Sleep tight.

No less an arbiter of reality than Carl Sagan hailed the show as a “public service … in which paranormal claims are systematically investigated and every case is found to be explicable in prosaic terms.” Later variations of the show tried tweaking the formula. Some featured real monsters (including a 1985 miniseries titled The 13 Ghosts of Scooby-Doo, starring Vincent Price as the warlock Vincent Van Ghoul). One, A Pup Named Scooby-Doo, recast the gang as elementary-school-aged. And characters were regularly subtracted or added—notably Scrappy-Doo, Scooby’s pint-size and pugnacious nephew. But the show consistently returned to its core premise.

Given that Nancy Drew and the Hardy boys had long since established the template of liberated teens outsmarting adult crooks, surely the show’s enduring success rests on more than that. Having a friendly dog involved has helped, certainly, though placing a Great Dane front and center is no guarantee of universal popularity, as Marmaduke fans will sadly inform you. A more telling clue, I think, can be found in the show’s timing. It debuted during a period of acute generational conflict and anxiety: the Vietnam/Nixon years, the “Never trust anyone over 30” years. Whether by accident or design, the makeup of the Mystery Inc. gang played perfectly into that moment.

A fundamental division has always prevailed within the group, occasionally hinted at but rarely made explicit, between Fred and Daphne on the one hand and Velma and Shaggy/Scooby on the other. The former looked and sounded older; the idea that Fred and Daphne were a couple (or an ex-couple) has been frequently suggested. And how else to account for that deepest mystery of the Scoobyverse—Fred’s fondness for his orange ascot? On some level, viewers are intended to see him as a grown-up. Daphne is a slightly more complicated case. But her maybe-relationship with Fred, her overt sexualization (her outfits, unlike Velma’s, are aggressively formfitting), and the eventual revelation that her family wealth supports Mystery Inc. clearly position her as the second quasi-adult in the group. She even has a scarf that mirrors Fred’s ascot—neckwear as a signifier of maturity.

By contrast, Velma, who is cited as the youngest of the gang, stands out as the quintessential TV representation of the smart, awkward teenager, right down to the glasses without which she is virtually blind. She has also been rumored for decades among fans to be gay, or at least bisexual. James Gunn, who wrote the screenplay for the 2002 live-action film, said he was “pretty sure” Velma is gay; Linda Cardellini, who played the character, described her sexuality as “a little ambiguous.” A kiss—relatively chaste—between Velma and Daphne was even shot for the film as a kind of inside joke, though it didn’t make the final cut.

Shaggy, meanwhile, has consistently been reputed to be a stoner, thanks to his slovenly look, his persistent case of the munchies, and his addiction, shared by Scooby, to a treat called “Scooby Snacks.” (The 2002 movie has fun with the stoner myth, too.) Throw in the fact that Shaggy was voiced for the better part of four decades by Casey Kasem, the DJ responsible for American Top 40, and the character was a walking bundle of youth-culture signifiers.

What better way to toy, below the surface, with the cultural tensions of the late ’60s and early ’70s? Juxtapose two borderline misfits in Velma and Shaggy—who are perhaps experimenting a little with sexuality and drugs—with two grown-up stand-ins for the more conventional sort in Fred and Daphne, and then let the offbeat characters consistently (yet all in good fun) one-up the establishment types. Even the show’s signature line, “And I would’ve gotten away with it if not for you meddling kids,” sounds like it could have been uttered by Richard Nixon.

But the genius of the young mystery hunters is that they were not prisoners of their era. (In fact, they were based explicitly on characters from an earlier show, The Many Loves of Dobie Gillis—one of the first TV series to make teenagers leading characters—in which a pre-Gilligan Bob Denver played Maynard G. Krebs, a kind of proto-Shaggy, right down to the chin scruff.) You don’t have to envision the group’s internal dialectic as the counterculture versus the establishment. The show’s longevity demonstrates that the metaphor works equally well as outsiders versus popular kids. Or, most primally, as children versus parents.

Indeed, over the past 50 years the Scooby-Doo characters have become almost archetypal, Joseph Campbell–worthy portraits of teenagerdom. Watch just about any ensemble teen show or movie, and you’ll find your Freds and Daphnes (often as foils or outright villains) and your Velmas and Shaggys. Perhaps no one applied this paradigm more self-consciously than the writer-director Joss Whedon in Buffy the Vampire Slayer, which winked at its predecessor by imagining a group of teen monster-fighters led by a superhero version of Daphne. Buffy and her pals even referred to themselves as the “Scoobies.” Whedon later claimed, tongue only partly in cheek, “All great fiction is Scooby-Doo-like.”

So we watch—and our kids watch, and eventually their kids will watch—four so-called teenagers and their Great Dane roam the countryside, pulling the mask off some fraudulent phantom or counterfeit creeper. They’ll be headed for your local multiplex soon enough. And fear not: They won’t ever really leave.

This article appears in the May 2020 print edition with the headline “The Secret of Scooby-Doo’s Enduring Appeal.”