Making a hit show comes with a lot of work and plenty of complications, and because of this, the folks that do reach the top of television have a whole lot to be proud of. Hit shows are few and far between, making the taste of victory even sweeter for television’s biggest stars.

Castle was a hit series during its time on the small screen, and Stana Katic and Nathan Fillion were exceptional in the lead roles. What some may not know, however, is that there were serious problems between the two while filming the show each season.

So, how bad did things get between Stana Katic and Nathan Fillion? Let’s take a look and see.

Nathan Fillion And Stana Katic Couldn’t Stand Each Other

Castle Series
Via Pinterest.com

On television, it can be easy for actors to mask their actual emotions in favor of what the script is calling for. They are, after all, professionals of their craft and need to be convincing while the cameras are rolling. During their time filming Castle together, Nathan Fillion and Stana Katic simply could not stand one another.

According to Us Weekly, a source from the show opened up about how bad things got between the pair, saying , “Stana Katic and Nathan Fillion completely despise each other. They will not speak when they are off set, and this has been going on for seasons now.”

Tensions on set are nothing new in the entertainment business, but things were apparently horrendous between the duo. Despite the great things they did while the cameras were rolling, the pair couldn’t find common ground and realized that they were better off by simply not being around one another.

The source who spoke to Us would also reveal that “Stana would go in her dressing room and cry. A lot of people who work on the show don’t like Nathan. It’s not just her.”

“The friction was very evident. Nathan has been nasty to Stana for a long time. Stana was a pro, just wanted to get in there and do her job,” the source continued.

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The Attended Couple’s Therapy As Co-Stars

Castle Series
Via hollywoodreporter.com

Of course, there are two sides to every story, and the truth usually lies somewhere in between. Nevertheless, the duo of Katic and Fillion had their issues on set and needed to seek professional help to try and mend things so that the show could continue to be a success on the small screen.

“This season, it got so out of hand they made Stana and Nathan go to couples counseling together,” said the source to Us Weekly.

Yes, couples therapy for co-stars. This does not seem like common practice in the business, and it made headlines when it as revealed. Sure, it is impossible to have everything run smoothly on set at all times, but how often do co-stars actually need to go to therapy to make things work while filming?

This situation just goes to show what life can be like behind the scenes of a popular show. There is plenty of drama that seeps into the headlines, but we never get the full picture, as most people are willing to stay tight-lipped about stuff that would make the studio or a performer look bad.

Related: Nathan Fillion Might Be Single, But His Love Life Is Not Boring

The Show Was Still A Huge Success

Castle Series
Via deadline.com

Despite all of the issues that Stana Katic and Nathan Fillion had while filming Castle together, the duo still made incredible things happen on the small screen. They both possess a ton of talent and made sure to bring their best for each episode of the show.

In total, the show ran for 8 seasons and a total of 173 episodes, making it a true winner. Fillion and Katic were both pulling down sizable salaries for their time on the show, and while they did not like working together, we cannot imagine that they have regrets about starring on a hit show.

Upon her departure from the show, Katic would thank the fans and crew, saying, “Your devotion to our show has carried us for these unforgettable 8 seasons. I’m lucky to have met and worked with for the lot of you. I will always be grateful.”

On social media, Fillion would speak highly of his co-star, saying, “Stana has been my partner all this time, and I thank her for creating the character Beckett who will live on for all of us as one of the greatest police officers on television. I wish her well, and have no doubt she will succeed in everything she pursues. She will be missed.”

Related: 15 Co-Star Feuds That Were Totally Fake

Castle was a terrific show, despite everything that was plaguing it behind the scenes.

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