To say that fans were disappointed when Castle was canceled would be an understatement. The show premiered in 2009 and lasted for eight seasons before it was canceled in 2016, despite the fact that a ninth season had been announced. One of the things that was rumored to be the cause of the cancelation was the deteriorating relationship between the stars, Nathan Fillion and Stana Katic.RELATED: What Really Happened Between Nathan Fillion And Stana Katic?It's been a few years since the show ended now, it's not irrational to assume that things are probably not as bad as they were said to be back then. Have they finally buried the hatchet?

6 Nathan Fillion And Stana Katic Reportedly Couldn't Stand Each Other

It's obvious that most on-screen relationships aren't the same in real life, but when it came to Nathan Fillion and Stana Katic, it seems their love and chemistry were not only fake but also the complete opposite of reality. These two actors convinced Castle fans that they were in love, but off the air, they reportedly ignored each other at best and were at each other's throats at worst.

"Stana Katic and Nathan Fillion completely despise each other," a source shared with Us Weekly. "They will not speak when they are off set, and this has been going on for seasons now."

5 They Even Went To Couples Counseling

Because Castle was such an important project for both of them, neither Nathan nor Stana was willing to let their personal issues get in the way of the development of the show. But of course, if conflicts kept arising and their personalities kept clashing, they could only go on ignoring it for so long. Added to that, they weren't only affecting their performances, but also the way everyone involved felt during the shootings.

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Allegedly, one of the solutions the production came up with was sending them to couples counseling. This was revealed by an insider source. One can only imagine how that went down.

4 Rumors Of Nathan Fillion Bullying Stana Katic

As the filming of Castle progressed, things between Nathan and Stana didn't get any better. In fact, the tension only seem to get stronger, and apparently, it wasn't just incompatibility anymore. There were rumors that Nathan was the one responsible for most of the conflicts on set, and that he was just outright bullying Stana.

"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," an insider told Us Weekly. "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."

3 Stana Katic's Departure From 'Castle'

When Stana Katic's contract wasn't renewed for the eighth season of Castle, it confirmed fans' suspicions that things had finally gone off the rails on set. But surprisingly, it apparently had nothing to do with her issues with Nathan Fillion. In fact, she was surprised when she was told she would not be returning to the show. She obviously wasn't happy about it, but looking back, she has no hard feelings.

"I’m actually still not clear on the thought process behind the way that it went down. It hurt, and it was a harsh ending, but now, nearly two years later… I met so many beautiful people on that project, and we collaborated on something really unique in that it’s not every day that you get a show, or a series, that has eight seasons and that it was a hit for the network," she explained. She then went on to add that, "It was a formative experience, and we told a love story that I feel moved people, touched people, and I can’t be anything but glad that I was a part of something like that. I hope it remains something special in viewers’ minds forever."

2 Nathan Fillion's Reaction To Stana Katic Being Fired

Whether or not Nathan was involved in the process of deciding not to renew Stana's contract remains a mystery, but he was very gracious about it regardless. When the news about Stana being written out of the show came out, he shared a kind message about her contribution to Castle and her talents.

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"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," he posted on Twitter. "I wish her well, and have no doubt she will succeed in everything she pursues. She will be missed."

Whatever their problems were, it seems they were able to put them behind them in the end.

1 What Happened When The Show Was Canceled?

Stana being fired didn't end up being such a big deal, since the show was canceled shortly after. Despite the seemingly unending conflicts that surrounded the making of the show, it doesn't look like either of the stars have any negative feelings towards their time on Castle. Both Nathan and Stana had nothing but beautiful things to say after the cancelation was announced.

"Dear Castle fans, cast & crew, your devotion to our show has carried us for these unforgettable 8 seasons," Stana said. "I'm lucky to have met & worked with & for the lot of you. I will always be grateful." For his part, Nathan said that "All things must end. It has been an honor working with the men and women of Castle. I am truly amazed at what we’ve done. Thank you all."

It's impossible to know whether Stana and Nathan had an actual conversation where they hashed out their disagreements and parted amicably, but given their last interactions and the way they talk about their time on the show, it's probably safe to say there is no bad blood between them.

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