The Big Bang Theory Season 4 Episode 8

This episode's end titles has Chuck Lorre's Vanity Card #311.

As of this episode, Mayim Bialik is elevated to the main cast, but is only credited when she appears.

During the West Coast airing of this episode, Wil Wheaton tweeted the exact tweets Sheldon read of his on-screen persona as they aired, though the @sheldoncooper account he mentions is actually not created or endorsed by the show.

This episode involved a late-night shoot on the Warner Bros. backlot, a rarity for the series. During the filming, co-creator Bill Prady, stars Simon Helberg and Kunal Nayyar, and guest Wil Wheaton were all active on Twitter, posting comments on—and pictures of—the proceedings.

International Airdates: United Kingdom: December 23, 2010 on E4; Turkey: October 4, 2011 on CNBC-e; Czech Republic: November 16, 2011 on Prima COOL; Slovakia: November 30, 2011 on Markiza

Because of her broken leg. Kaley Cuoco (Penny) is shown working as The Cheesecake Factory's bartender again, instead her normal job as a waitress. Also, a body double is used when Penny storms off near the end of the episode.