Leonard and Penny throw a cocktail party but are their friends adult enough to enjoy it on The Big Bang Theory? "The Closet Reconfiguration" is the 19th episode of the show's sixth season.
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The Big Bang Theory Season 6 Episode 19 Quotes

Bernadette: Sheldon, I've been cooking all day.
Sheldon: Well ... now don't you feel silly.
Bernadette [to Howard]: Show him the closet

Bernadette: You can't just throw everything in the closet.
Howard: Hey, you can tell what to do or you can tell me how to do it, but you can't do both. This isn't sex.