Quick recap
Leonard and Penny's first date doesn't turn into a relationship, so they stay friends. Penny grows closer to Sheldon, who reluctantly keeps a secret of hers, and becomes part of the gang's routine. Leonard dates Leslie Winkle and then Stephanie, a doctor who moves into his place without him noticing. Penny dates Stuart, the comic book store owner. Leonard's psychiatrist mother, Beverly, pays a chilly visit. Howard still strikes out with women. In the finale, Sheldon lands funding for a three-month North Pole expedition and takes Leonard, Howard and Raj. Penny says goodbye to Leonard with a hug, and something hangs in the air.
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