A woman who moves into an apartment across the hall from two brilliant but socially awkward physicists shows them how little they know about life outside of the laboratory.
In season five, episode nineteen, The Big Bang Theory: The Weekend Vortex (2012), for some reason, Kaley Cuoco is omitted from the credits, despite appearing in the episode. In the beginning of the episode, while Leonard, Howard, and Raj are walking up the stairs, the credits start with "Starring Johnny Galecki, Jim Parsons, Simon Helberg, Kunal Nayyar..." instead of "Starring Johnny Galecki, Jim Parsons, Kaley Cuoco, Simon Helberg, Kunal Nayyar..."
Sheldon:
I'm not crazy. My mother had me tested!
The dead bolt on Penny's apartment door is clearly in the lock position in one scene, yet she opens the door without unlocking it.
One of the final cards to appear in the credit sequence is the vanity card for Chuck Lorre Productions. In keeping with his practice on "Dharma and Greg" and "Two and a Half Men", there is a different message on the card each week, written by Chuck Lorre himself.
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