Nathan Fillion played himself in one episode of The Big Bang Theory when Raj and Leonard approach him at a deli. Nathan is most recognized for his work in the ABC series Castle as Richard Castle and as Captain Malcolm Reynolds in the sci-fi series Firefly. He has also played a few different roles in each installment of The Guardians of the Galaxy franchise.
In the last few years, the actor had started going out with Baywatch actress Krista Allen, who was previously married twice. She also dated George Clooney for a couple of years until 2004. However, Fillion and Allen went their separate ways in 2020.
Kaley Cuoco and Henry Cavill
You could go as far as saying that the following relationship is Leonard Hofstadter's worst nightmare. At one point, Kaley Cuoco dated actor Henry Cavill, who is most famous for his portrayal of Superman. However, the romance only lasted for a whole 10 days - making it one of the shortest ones on this list.
Their brief fling was just before Kaley met her now ex-husband Ryan Sweeting (who she married after just three months of dating.) The paparazzi were all over this superhero “couple.” Kaley once remarked during an interview, “I had no one following me until I met Superman.” We find that hard to believe.
Johnny Galecki and Kelsey Harper
As you know by now, Johnny Galecki plays one of the main protagonist geeks in the show, Dr. Leonard Hofstadter. In the show, he dated blonde bombshell Penny, and eventually tied the knot with her in what many believe is one of the most wonderful romances in the history of television.
Galecki has had several other roles including acting as David Healy in Roseanne. He dated actress Kelsey Harper who also had some big roles of her own. Sadly, it didn't last too long, and she has now retired and works as a florist, which we are guessing is a lot more peaceful!
Kaley Cuoco and Ryan Sweeting
Kaley Cuoco got a lot of media attention when she got engaged to former professional tennis player, Ryan Sweeting after only three months of dating. Apparently, Cuoco was very sure that she found the one. Kaley had said, “From day one I just knew immediately and it’s been magic.”
However, it seems that she was a little off in her estimation. The two got married in 2013 but contrary to Kaley’s previous confidence about the relationship, the two divorced after just two years. There were rumors spreading of divorce three months before they broke up, but Cuoco denied such a thing.
Kaley Cuoco and Christopher French
There have been a string of famous faces that Kaley Cuoco has been linked with outside of marriage. For example, she dated Christopher French, a founder of the LA-based band Annie Automatic from 2011-2012. He has composed music for a few series such as Young & Hungry and Life Flight as well.
They looked pretty happy in the photo above, but ultimately, it was a brief romance. Christopher French is now married to Ashley Tisdale (from the High School Musical movies), whom he met in 2014. He proposed to her on the top of the Empire State Building. The musical duo got married in 2014.