Before starring in "The Big Bang Theory," Johnny Galecki was best known to television audiences for his role as David in the long-running comedy series "Roseanne," for which he won a Young Artist Award. His other television series credits also include a recurring role in "My Boys" and guest appearances in "My Name is Earl." Galecki's feature film credits include "Hancock," opposite Will Smith, Charlize Theron and Jason Bateman, "Crystal," "Bookies," "Vanilla Sky," "Bounce," "Playing Mona Lisa," "The Opposite of Sex," "I Know What You Did Last Summer," "Suicide Kings" and "National Lampoon's Christmas Vacation."
Jim Parsons has appeared on the big screen in "School for Scoundrels" and "Heights." He has also played pivotal roles in several independent films, including "Garden State," "Gardner of Eden" and "The Great New Wonderful." Parsons' other television credits include recurring roles in the series "Judging Amy" and "Ed."
Prior to "The Big Bang Theory," Kaley Cuoco was best known to television audiences for her role as Bridget Hennesy in the series "8 Simple Rules." She won a Teen Choice Award for her role and was featured in TV Guide's "Generation Now" and Vanity Fair's "Teenage It" lists.
Simon Helberg's television credits include guest starring appearances in "MAD TV," "Reno 911," "Joey" and "Studio 60 on the Sunset Strip." His feature film credits include "Van Wilder," "Old School," "Good Night, and Good Luck" and "For Your Consideration." He will soon appear in the feature films "Mama's Boy" and Judd Apatow's "Walk Hard."
Kunal Nayyar's role in The Big Bang Theory is his first as a regular on a television series. He had a guest starring role on NCIS. Nayyar is writing his first feature film, and his critically acclaimed play, "Cotton Candy," continues to run in New Delhi.