Quick recap
The expedition comes home, and Sheldon learns his friends faked the data to spare him a failure. Humiliated, he flees to Texas. Leonard and Penny finally start dating. Penny sets Howard up with Bernadette, a coworker studying microbiology, and they become a couple. Sheldon gets into a prank war with Kripke and faces Wil Wheaton at a card tournament. When Leonard says 'I love you' and Penny doesn't say it back, they break up. In the finale, Penny shows up with a new boyfriend, Zack, dumps him and drunkenly tries to get back with Leonard. Meanwhile, Howard and Raj sign Sheldon up for a dating site, and he meets Amy Farrah Fowler.
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