![The Big Bang Theory Season 9 Episode 17 The Big Bang Theory Season 9 Episode 17](https://image.tmdb.org/t/p/w185/eKDvR1vYLCE08K1h0KUfHNliD8T.jpg)
The Big Bang Theory Season 9 Episode 17
After more than nine years together, the gang finally celebrates Sheldon’s birthday, surprising him with a special guest.
Serie: The Big Bang Theory
Director: Mark Cendrowski, Nikki Lorre
Guest Star: Adam West, Christine Baranski, John Ross Bowie, Kevin Sussman, Sara Gilbert, Stephen Hawking, Wil Wheaton