Al Santos

Onscreen chemistry with Penny and Leonard on "The Big Bang Theory" came from a very real place, as Kaley Cuoco and Johnny Galecki's onscreen chemistry as "The Big Bang Theory" came from a very real place. Cuoco talked about her former crush on Galecki in an excerpt from the forthcoming book "The Big Bang Theory: The Definitive Inside Story of the Epic Hit Series," published by Vanity Fair on October 3rd. "I was so not even hiding it," she said in Vanity Fair. "He has such swagger." Both of us were dating at the time, but I only had eyes for Johnny.' Neither actor has publicly announced who they were with romantically at the time of the show's debut, though Cuoco briefly dated Al Santos in 2007, the first year "The Big Bang Theory" aired. However, their attraction, despite their strong friendships, didn't fade. Cuoco said, "It was clear there was always something there." "We were all crashing on each other and chemistry was present." That was the whole first season before we really got together for real."