Big Bang Theory: The Infestation Hypothesis

"The Infestation Hypothesis" is the second episode of season five of the comedy series The Big Bang Theory and the nineteenth episode of the series overall. It was directed by Mark Cendrowski with a teleplay written by Bill Prady and Lee Aronsohn based on a story treatment by Chuck Lorre. It first aired on CBS on Monday, September 22nd, 2011. In this episode, Leonard Hofstadter is looking to get back into the dating game. Discouraged that things never moved forward with Penny, Leonard calls upon the affection of his occasional sexual stress release partner, Leslie Winkle, which ultimately makes Penny jealous. And Sheldon Cooper complains about the historical inaccuracies of a local Renaissance Fair.