Johnny Galecki Leonard Actor Jim Parsons Sheldon Actor Kaley Cuoco Penny Actor Simon Helberg Wolowitz Actor Kunal Nayyar Koothrappali Actor Mayim Bialik Amy Actor Melissa Rauch Bernadette Actor Brian George Dr. V.M. Koothrappali Guest Star Dean Norris Colonel Richard Williams Guest Star Brian Posehn Bert Kibbler Guest Star Brandon Jones The Flash Guest Star Chuck Lorre Executive Producer Bill Prady Executive Producer Steven Molaro Executive Producer, Writer Saladin K. Patterson Writer Tara Hernandez Writer Steve Holland Writer Maria Ferrari Writer Jeremy Howe Writer Mark Cendrowski Director