Penny acts strangely after her breakup with Pete on Happy Endings. "The Storm Before the Calm" is the 18th episode of the show's third season.
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Happy Endings Season 3 Episode 18 Quotes

What she did was a strong move by a strong woman. She's basically Mary J. Blige.

Jane

Those are cool. And this is coming from a guy who wore a bandana around his jeans leg in high school, so I know what I speak of.

Dave