The Big Bang Theory

American sitcom The Big Bang Theory centers around friends Leonard Hofstadter (Johnny Galecki), Sheldon Cooper (Jim Parsons), Penny Teller (Kaley Cuoco), Howard Wolowitz (Simon Helberg) and Raj Koothrappali (Kunal Nayyar). Supporting characters Amy Farrah Fowler (Mayim Bialik), Bernadette Rostenkowski (Melissa Rauch) and Stuart Bloom (Kevin Sussman) were promoted to main roles throughout the series.

With four of the main characters being scientists, the series has featured famous guest stars including astrophysicist and Nobel laureate George Smoot, chemical engineer and Nobel laureate Frances Arnold, cosmologist Stephen Hawking and Bill Nye.

The sitcom aired on CBS from 2007 to 2019 with a total of 12 seasons. It received four Emmy nominations for Outstanding Comedy Series, and Parsons won four Emmys for his performance on the show. A spinoff series centered around Parsons’ character titled Young Sheldon debuted in 2017 and features Parsons narrating as adult Sheldon.