One night in the late 1950s, just out of the Navy and looking for work, Ken Spears returned home to Los Angeles and met up with an old family friend.
Mr. Spears later told entertainment writer Michael Stailey that he didn’t realize Hanna, a founder of the animation studio Hanna-Barbera, was in the cartoon business. But when the co-creator of “Tom and Jerry” told him that he was paying $104 a week, Mr. Spears agreed to join the studio’s editorial department, working on shows including “Ruff and Reddy,” “Huckleberry Hound” and “The Flintstones.”
Over the next few years, he participated in nearly every aspect of cartoon production, including music, sound effects, editing and writing. He also began a lasting creative partnership with his colleague Joe Ruby, with whom he created a mystery and comedy series involving four teenage detectives, a cowardly Great Dane and a psychedelic van called the Mystery Machine.
“We were worried it wouldn’t last but one season, much less 38 years,” Mr. Spears later said. “It was up against ‘The Hardy Boys’ on NBC and we thought we’d get clobbered in the ratings.”
Instead, “Scooby-Doo, Where Are You!” became a pop-culture phenomenon, premiering on CBS in 1969 and remaining on-screen in one form or another for the next five decades. Scooby-Doo characters appeared in more than a dozen television series and two live-action films and were licensed for underwear, dog biscuits, action figures and fruit snacks.
But the creators received little credit and no major payday, in part because the franchise originated at a company known as “the General Motors of animation,” in an era when few individual artists were promoted and cartoons were considered work for hire. Scooby’s creators ultimately left to start a studio of their own.
Mr. Spears was 82 when he died Nov. 6, less than three months after Ruby’s death on Aug. 26. His son Kevin Spears said he died at an assisted-living center in Brea, Calif., of complications of Lewy body dementia.
The idea for Scooby-Doo dated back to late 1968, said Kevin Sandler, a professor of film and media studies at Arizona State University who is writing a book about the show. In the wake of the Robert F. Kennedy assassination, the country was in a “moral panic,” he said, with reform-minded magazines and civic groups condemning the violent, action-packed cartoons that dominated children’s television programming.
In search of a more gentle cartoon to anchor his Saturday morning lineup, CBS executive Fred Silverman enlisted Hanna-Barbera to create a program modeled after 1940s radio series like “I Love a Mystery” — but with kids, as in his network’s new musical sitcom “The Archie Show.” Producer Joseph Barbera told Mr. Spears and Ruby to get to work.
As Mr. Spears told the story, they were leaving Barbera’s office when Ruby “snapped his fingers, sticks his head back inside and says, ‘Joe, is it okay to put a dog in it, because we know Freddy Silverman likes dogs?’ And Joe Barbera said, ‘Sure, do anything you want.’ ”
Tentatively named “Mysteries Five,” the show went through a lengthy development process, with the teenage characters initially performing in a rock band and accompanied by a feisty sheepdog character. The dog became an oversized Great Dane, modeled on actor and comedian Bob Hope, and was brought to life by animator Iwao Takamoto, who had previously created the Jetsons’ dog Astro.
Scooby-Doo’s name came from Silverman, who had heard Frank Sinatra scatting “doo-be-doo-be-doo” on a recording of “Strangers in the Night,” and whose own name was used for Fred, the group’s ascot-wearing leader. The gang was rounded out by Daphne (whose catchphrase was “Jeepers!”), Velma (“Jinkies!”) and Shaggy (“Zoinks!”), Scooby’s bell-bottomed sidekick.
Originally voiced by radio broadcaster Casey Kasem, Shaggy always seemed more interested in snacking — fans speculated he was a stoner, which Mr. Spears denied — than in tracking down cow rustlers, art forgers and other petty crooks who disguised themselves as vampires or abominable snowmen.
Mr. Spears and Ruby wrote or story-edited all but four of the show’s original 25 episodes, honing the chemistry between Shaggy and Scooby and frequently sending Fred and Daphne off on their own so that they could focus on the other, more interesting characters.
“The timing’s the thing: You can’t dawdle,” Mr. Spears told the New York Times in 1969, explaining the Hanna-Barbera approach to writing. “Anything from comedy to drama here is mainly rapid-fire attack. Otherwise, the kids’ll turn the channel on you.”
Mr. Spears and Ruby also created Hanna-Barbera programs such as “Dynomutt, Dog Wonder” and “Jabberjaw,” about a great white shark who plays the drums in an underwater rock band, and worked as story supervisors on “Josie and the Pussycats.” In 1977 they set up their own studio, Ruby-Spears Productions.
While Ruby worked on the creative side, Mr. Spears focused on the financial and production aspects, working on shows including “Alvin and the Chipmunks,” “Mister T” and “Thundarr the Barbarian,” a post-apocalyptic fantasy series that was partly designed by Marvel comics legend Jack Kirby.
He also took on more mundane tasks like building animation desks, which he said he made himself, “just like Bill Hanna did.” Mr. Spears had befriended Hanna’s son while growing up and described the man who brought him into the cartooning business as “kind of a surrogate father to me.”
The second of five children, Charles Kenneth Spears was born in Los Angeles on March 12, 1938. His mother died soon after he was born, and his father worked for NBC as a radio host and producer, then became a real estate agent.
Mr. Spears’s first wife, the former Sandra Mathison, died in 2007. A second marriage ended in divorce. In addition to his son Kevin Spears, of Yorba Linda, Calif., survivors include another son, Chris Spears of Anaheim, Calif.; two brothers; two sisters; five grandchildren; and three great-grandchildren.
In a phone interview, Kevin Spears recalled that his father was disappointed but “never bitter” that he didn’t receive more credit or compensation for co-creating Scooby-Doo. “He just wasn’t that kind of person,” he said. “He felt he made a decent living.”
On the show’s 30th anniversary, Mr. Spears told the Orange County Register that he and Ruby were surprised the franchise had lasted so long. “These things come along once in a lifetime,” he said. “It’s amazing — our grandchildren watch the show. Who could have guessed?”
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