Shearer is known for his work as a voice actor on "The Simpsons". Matt Groening, the creator of the show, was a fan of Shearer's work, while Shearer was a fan of a column Groening used to write. When approached by Groening to be in the series, Shearer was initially reluctant because he thought the recording sessions would be too much trouble. He felt that voice acting was "not a lot of fun" as, traditionally, voice actors record their parts separately. He was told that the actors would record their lines together, and after three phone calls for executive producer James L. Brooks, Shearer was convinced to join the cast of "The Simpsons". Shearer's first impression of "The Simpsons" was that it was funny. He–who thought it was a "pretty cool" way to work–found it peculiar that his fellow cast members were adamant about not being known to the public as the people behind the voices.