25% off Plex Pass for Fan Friday

Personal media fans, this one’s for you.

Learn More.

The Big Bang Theory

The Alien Parasite Hypothesis

S4 E10    Dec 8, 2010    20m    TV-PG
7.6
Amy finds she has sexual feelings for Penny's ex, while Koothrappali and Wolowitz try to prove who would be the better superhero.
Where to Watch The Alien Parasite Hypothesis
Cast of The Alien Parasite Hypothesis
  • Johnny GaleckiLeonard Hofstadter
  • Jim ParsonsSheldon Cooper
  • Kaley CuocoPenny
  • Simon HelbergHoward Wolowitz
  • Kunal NayyarRajesh Koothrappali
  • Melissa RauchBernadette Rostenkowski
  • Mayim BialikAmy Farrah Fowler
  • Brian Thomas SmithZack Johnson
 
  •   
  •   
  •   
  •   
  •   
  •   
  •   

Take Plex everywhere

Watch free anytime, anywhere, on almost any device.
See the full list of supported devices