The Big Bang Theory
The Alien Parasite Hypothesis
Season 4, Episode 10 · Aired 2010-12-09
Synopsis
Amy finds she has sexual feelings for Penny's ex, while Koothrappali and Wolowitz try to prove who would be the better superhero.
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