It turned out the on-screen romance between Penny and Leonard translated into off-screen relationship although nobody knew.
Actress Kaley Cuoco has stunned Hollywood by revealing she and her "The Big Bang Theory" co-star Johnny Galecki secretly dated for two years. The TV stars fell in love when they started shooting the hit comedy and managed to keep the romance under wraps by never going out in public together.
She says, "We dated for almost two years... It was a wonderful relationship but we never spoke a word about it and never went anywhere together." Cuoco tells Watch magazine the romance ended at the beginning of the year, but she's still good friends with her ex. She adds, "We weren't destined to be together... We accepted it."
In the comedy series, Cuoco portrays Penny who dates Galecki's Leonard on and off.