Brian Posehn as Bert Kibbler
Brian Posehn breathed life into the character of Bert Kibbler, a fan favorite known for his endearing personality and social awkwardness. While Amy works in Cal Tech’s labs, Bert develops feelings for her even though he knows she is dating Sheldon and is oblivious to Bert’s affections. A geologist by profession, Bert often attempts to make jokes with rock puns that few people find amusing. However, Bert’s fortunes change when he wins the MacArthur Fellowship, an honor previously bestowed on Sheldon. This moment marks a turning point for Bert’s character, much to Sheldon’s chagrin.