Ken Spears was known throughout the world of animation as the co-creator of the Scooby-Doo series, and as the co-founder of Ruby-Spears Productions with his longtime collaborator  Joe Ruby. Sadly, Spears has passed away at the age of 82 — less than three months after Ruby passed away at the age of 87. According to Variety, Spears’ cause of death was “complications related to Lewy body dementia.”

Spears broke into animation at Hanna-Barbera in its editing department, where he first met and worked with Ruby. Together, Spears and Ruby created numerous shows at Hanna-Barbera, including JabberjawDynomutt, and their most enduring creation, the original Scooby-Doo, Where Are You! As the story goes, Ruby and Spears were asked to create a mystery show for kids for CBS. What they made became the template for decades of similar series.

The partners eventually left Hanna-Barbera to start their own company, Ruby-Spears, which produced many of the 1970s and ’80s most beloved animated series. Their work includes Thundarr the Barbarian, the 1980s revival of Alvin and the Chipmunks, and Mr. T’s cartoon series:

Spears and Ruby leave behind an enormous legacy in the world of 20th century pop culture. Their company’s catalog now belongs to Warner Bros. and Cartoon Network, which continues to rerun their old shows and produce new versions of their classics like Scooby-Doo. As long as teens and wacky sidekicks solve mysteries in cartoons, both Ken Spears and Joe Ruby will be remembered.

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