Sheldon-------Jim Parsons
Leonard-------Johnny Galecki
Katie---------Amanda Walsh
Gilda---------Iris Bahr
The show's initial pilot, developed for the 2006–07 television season, was substantially different from its current form. Only Johnny Galecki and Jim Parsons were in the cast, and the female lead, Katie, was envisioned as "a street-hardened, tough-as-nails woman with a vulnerable interior".[21] Katie was played by actress Amanda Walsh[22] They also had a female friend called Gilda (played by Iris Bahr). The show's original theme music was also different, using Thomas Dolby's hit "She Blinded Me With Science". The show was not picked up, but the creators were given an opportunity to revise the show, bringing in the remaining leading cast and retooling the show to its current format. The original unaired pilot has never been released on any official format, but copies of it are floating around the internet with various collectors. On the evolution of the show, Lorre bluntly admitted "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 that original pilot, maybe on a DVD, Lorre said "Wow that would be something, we will see. Show your failures..."