Johnny Galecki Leonard Hofstadter Actor Jim Parsons Sheldon Cooper Actor Kaley Cuoco Penny Actor Simon Helberg Howard Wolowitz Actor Kunal Nayyar Raj Koothrappali Actor Sara Gilbert Leslie Winkle Actor Kevin Sussman Stuart Bloom Guest Star Jodi Lyn O'Keefe Mikayla Guest Star Carol Ann Susi Debbie Wolowitz Guest Voice Sara Rue Dr. Stephanie Barnett Guest Star Mark Harelik Dr. Eric Gablehauser Guest Star Charlie Sheen Charlie Sheen Guest Star Michael Trucco Dr. David Underhill Guest Star John Ross Bowie Barry Kripke Guest Star Brian George Dr. V.M. Koothrappali Guest Star Emily Happe Kathy O'Brien Guest Star Elena Campbell-Martinez Maria Guest Star Alice Amter Mrs. Koothrappali Guest Star Livia Treviño Lourdes Guest Star Jade Zdanow Rebecca Guest Star Chuck Lorre Executive Producer, Writer Bill Prady Executive Producer, Writer David Goetsch Writer, Executive Producer Daley Haggar Writer Steven Molaro Writer, Supervising Producer Lee Aronsohn Writer Stephen Engel Writer, Consulting Producer Eric Kaplan Writer, Executive Producer Mark Cendrowski Director Richard Rosenstock Writer Tim Doyle Writer Jennifer Glickman Consulting Producer Mona Garcea Coordinating Producer Peter Chakos Film Editor