The Big Bang Theory
The Celebration Experimentation
Season 9, Episode 17 · Aired 2016-02-25
Synopsis
After more than nine years together, the gang finally celebrates Sheldon's birthday, surprising him with a special guest.
In the series
This episode is part of The Big Bang Theory (2007–2019) on CBS.
Nerd culture goes multi-cam prime-time global.
Key cast
- Johnny Galecki as Leonard Hofstadter
- Jim Parsons as Sheldon Cooper
- Kaley Cuoco as Penny
- Simon Helberg as Howard Wolowitz
- Kunal Nayyar as Raj Koothrappali
- Mayim Bialik as Amy Farrah Fowler