![The Big Bang Theory Season 9 Episode 21 The Big Bang Theory Season 9 Episode 21](https://image.tmdb.org/t/p/w185/eKDvR1vYLCE08K1h0KUfHNliD8T.jpg)
The Big Bang Theory Season 9 Episode 21
Everyone must choose sides when a small argument between Leonard and Sheldon erupts into a heated fight during a group get-together.
Serie: The Big Bang Theory
Director: Anthony Joseph Rich, Mark Cendrowski, Nikki Lorre
Guest Star: Kevin Sussman