Quick recap
Physicists Leonard Hofstadter and Sheldon Cooper share an apartment in Pasadena and work at Caltech with their friends Howard Wolowitz, an engineer, and Raj Koothrappali, an astrophysicist who can't talk to women. Everything changes when Penny, an aspiring actress waiting tables, moves in across the hall. Leonard falls for her instantly. Sheldon gets fired, and his mother, Mary, comes from Texas to set things straight. Leonard dates coworker Leslie Winkle, Howard hits on Penny with zero success and Raj only talks to her when drunk. In the finale, Penny breaks up with her boyfriend, Sheldon explains Schrödinger's cat and Leonard finally asks her out.
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