From 2007 to 2019, CBS’s “The Big Bang Theory” provided audiences with the best of science, the shared love of different genre fandoms, and plenty of laughs along the way. Like all great sitcoms, it was the cast of characters that gave the series its addictive appeal.

The comedic charisma between best friends Sheldon Cooper (Jim Parsons) and Leonard Hofstadter (Johnny Galecki), along with next-door neighbor Penny (Kaley Cuoco), was the foundation upon which the program stood.

Some “Big Bang Theory” fans elicited strong feelings about Penny and Leonard’s wedding, but despite the mixed reaction, the event was a welcome relief after a decade of “Will they or won’t they?”

In recent years, both performers have come forward to reveal they were in a relationship together during the first couple of years of the show. Cuoco revealed the secret relationship to CBS Watch! Magazine in 2010 (per ET Online), roughly a year after they parted ways.

In a joint interview with Vanity Fair, Kaley Cuoco and Johnny Galecki revealed the episode where they developed strong feelings for one another in real life. Season 1, Episode 14, “The Nerdvana Annihilation,” continued the running thread of Leonard’s crush on Penny.