• Leonard and Leslie

Leonard and Leslie (Photo : Facebook)

Fans of "The Big Bang Theory" have long wondered what happened to Leslie Winkle (Sara Gilbert), who played Sheldon Cooper's (Jim Parsons) archenemy and Leonard Hofstadter's (Johnny Galecki) love interest in the early seasons.

As the premiere date for season 9, slated on September 21, gets closer, many fans are starting to wonder what will happen to Leonard and Penny's (Kaley Cuoco) relationship. In the season 8 finale, fans saw the two driving to Las Vegas to finally get married after being pressured by Sheldon to set a wedding date.

Like Us on Facebook

En route to Vegas, Leonard, admitted to Penny that he cheated on her while he was on the ship working for Stephen Hawking's team. Fans of the CBS series may remember that he also cheated on Raj's (Kunal Nayyar) sister Priya (Aarti Mann) in season 5.

Up until today, many are still wondering why Gilbert's character was written off the show. In season 2, she was upgraded as a series regular. However, five months later, she was fired from the show.

According to Entertainment Weekly, the writers had a difficult time writing about her. The publication reported that she will still be a recurring cast member on the show as she and "The Big Bang Theory" executive Chuck Lorre had a long-standing relationship since their "Roseanne" days.

However, since making an appearance in season 3's "The Cushion Saturation," Gilbert has not returned to the series. Since she left, two additional female scientists Amy (Mayim Bialik) and Bernadette (Melissa Rauch) joined the show.

Galecki and Gilbert dated when they were both on "Roseanne." In an interview with The Talk, the actress admitted that she realized that she was a lesbian after making out with her ex-boyfriend. She said that Galecki, however, kept her secret even after she started dating another woman 18 years her senior.