The Big Bang Theory

The Big Bang Theory is an American television sitcom that aired on CBS from September 27, 2007 to May 16, 2019. The series had a total of 288 episodes.

Plot
Although the show was not picked up, its creators were given an opportunity to retool it and produce a second pilot. They brought in the remaining cast and retooled the show to its final format. Katie was replaced by Penny (Kaley Cuoco). The original unaired pilot never has officially been released, but it has circulated on the Internet. On the evolution of the show, Chuck Lorre said, "We did the 'Big Bang Pilot' about two and a half years ago, and it sucked ... but there were two remarkable things that worked perfectly, and that was Johnny and Jim. We rewrote the thing entirely and then we were blessed with Kaley and Simon and Kunal." As to whether the world will ever see the original pilot on a future DVD release, Lorre said, "Wow, that would be something. We will see. Show your failures..."

Cast

 * Johnny Galecki as Leonard Hofstadter
 * Jim Parsons as Sheldon Cooper
 * Kaley Cuoco as Penny
 * Simon Helberg as Howard Wolowitz
 * Kunal Nayyar as Rajesh Koothrappali
 * Melissa Rauch as Bernadette Rostenkowski-Wolowitz (recurring season 3, starring seasons 4–12)
 * Mayim Bialik as Amy Farrah Fowler (guest star season 3, starring seasons 4–12)
 * Kevin Sussman as Stuart Bloom (recurring seasons 2–5, 7, starring seasons 6, 8–12)