Kaley Cuoco (Penny Hofstadter)
Penny Hofstadter, née Teller, appeared in all 12 seasons of the show. In the pilot episode, she grabs the attention of Leonard, who lives just across the hall, and he goes full Ted Mosby mode in an attempt to gain her attention and affection.
She admits that she’s a struggling actress and has to work at The Cheesecake Factor to make ends meet. Penny leaves her job at the dessert factory and becomes a pharmaceutical rep in Bernadette’s company. Throughout the series, Penny and Leonard have an up-and-down relationship, where they dated and broke up. In the ninth season, the couple finally tied the knot during a trip to Vegas.