The 10 Worst The Big Bang Theory Episodes
1. The Common Deterioration (Season 5 Episode 11)
When Raj is tasked with creating a message for NASA in the chance that any of their spacecraft encounter alien life, the gang argue as to what they think the message should be. Meanwhile, facing a cross roads in her career, Penny contemplates whether or not she should return to acting.
Why it sucks: It's painful to see that even after eight seasons, the writers can't decide on a good character development ark for Penny. Time after time her character faces this choice and it never seems to end making her seem increasingly more two dimensional. A few more examples of the laziness is when Leonard tells Raj to make sure to tell the aliens not to sit in Sheldon's spot and when Howard calls tech support, he rings Raj's number.
Adding to that, the alien message storyline had so much potential but ended in cliches about ET and Sheldon further alienating (heh) himself from the group.
What didn't suck: The ending when aliens fly past earth and come across Sheldon's video where he welcomes them to his home planet.