Behind-The-Scenes Scandals! A Look Back At 'Grey's Anatomy' Most Dramatic Exits Ever

Grey's Anatomy is one the longest running shows on cable television and will be going into its 14th season at the end of September. Having spanned over the course of 12 years — since 2005 — the show has endured its share of scandals and heartbreaks.

Almost all of the original cast members who were a big part of the show's success are now gone. Click through to see the most dramatic exits of the Grey's Anatomy cast over the years.

Grey's Anatomy is one the longest running shows on cable television and will be going into its 14th season at the end of September. Having spanned over the course of 12 years — since 2005 — the show has endured its share of scandals and heartbreaks.

Almost all of the original cast members who were a big part of the show's success are now gone. Click through to see the most dramatic exits of the Grey's Anatomy cast over the years.

Isaiah Washington who played Preston Burke got the boot in 2007 when he used the homophobic slur "f****t" in a heated argument with Patrick Dempsey in reference to fellow cast member T.R. Knight. That heated exchange led to chaos among production.

Washington had issued an apology and shot a PSA on behalf of the gay rights advocacy group GLAAD. The 54-year-old was also willing to sit with Diane Sawyer, a move ABC insiders were against. In the end, it was not enough to save his job.

T.R. Knight quit the show soon after in 2009, leaving fans shocked. His exit was nothing short of dramatic. In a falling out with the show's creator, Shonda Rhimes, Knight admitted he did not trust her.

"My five-year experience proved to me that I could not trust any answer that was given about George," Knight explained. "And with respect, I'm going to leave it at that."

Knight admitted that Rhimes was someone who discouraged him from coming out so close to the "Isiahgate" drama.

"I think she was concerned about having my statement come out so close to the initial event."

Rhimes denied those allegations. "I said, 'If you want to come out, that's awesome. We'll totally support that.' And then he went away, thought about it, and came back and said, 'I'm going to make this statement.' I remember saying to fellow executive producer Betsy Beers, 'This is our proudest day here. T.R. got to come out, and I got to say to him that it wouldn't affect his character' — because he was concerned that he was going to come out and George would suddenly be gay. I was like, 'We are not going to do that.' The idea that a gay actor can't play a straight man is insulting."

Knight attempted to stay on but remained unhappy with the direction his character, George O'mally, was heading towards. Specifically, Knight did not like the idea of his character cheating on his onscreen wife, Dr. Callie Ramirez, with fellow castmate, Katherine Heigl's character.

Heigl tried to convince Knight to stay, but ultimately made the decision to walk away from a 14 million dollar contract deal.

Fans were confused when Katherine Heigl followed suit after T.R Knight's exit. Heigl, who played the role of Izzy Stevens — the upbeat quirky doctor who ends up having hallucinations over her dead husband — thought her movie career would take off and made the decision to leave in 2010.

But drama was following Heigl long before she received leading movie roles. In 2008, she withdrew her name from consideration when she received an Emmy nomination for her role on the show because she didn't feel the writing was worthy of the award.

"I did not feel that I was given the material this season to warrant an Emmy nomination and in an effort to maintain the integrity of the academy organization, I withdrew my name from contention. In addition, I did not want to potentially take away an opportunity from an actress who was given such materials."

Rhimes opened up about the incident two year laters — in 2010 — while doing an interview with Oprah.

"On some level, it stung and on some level I was not surprised," Rhimes said. "When people show you who they are, believe them."

Heigl later discussed wanting to return to the show, but Rhimes was not on board.

Heigl's costar, Ellen Pompeo, who plays leading lady, Dr. Meredith Grey also spoke out on Heigl's departure from the show.

"When Katie left, it was tough," she said of her former costar's much-buzzed about departure. "You could understand why she wanted to go — when you're offered $12 million a movie and you're only 26. But Katie's problem is that she should not have renewed her contract. She re-upped, took a big raise and then tried to get off the show. And then her movie career did not take off."

Probably the most dramatic and shocking exit of the entire show was Patrick Dempsey who played Dr. Derek Shepard aka Mr. McDreamy on the hit series. Rumors swirled that Dempsey was fired for showing 'diva behavior' behind the scenes.

Dempsey had signed a $12 million contract for season 12, but his character was abruptly killed off at the end of season 11.

The rumors began to intensify when Rhimes went on the Larry Willmore show in 2015 and admitted to killing off a character before because she didn't like the person. Rhimes however, never confirmed if she was referring to Dempsey.

"We had a lot of discussions about it," Rhimes says. "It wasn't easy or fun, it is never easy or fun. We've been working really hard for a long time together. We're family. Those choices and those decisions are never easy for any of us."

Dempsey pinned his exit off the show as the opportunity to have a better quality life. "I think after a certain period of time, no matter how much money you make, you want control out of your own schedule," Dempsey, who is the father of three children said."It had been long enough. It was time for me to move on with other things and other interests. I probably should have moved on a couple of years earlier. I stayed a bit longer than I should have."

Perhaps the least scandalous of all, but the most heartbreaking exit was Sandra Oh who played Dr. Christina Yang on the show. The 46-year-old left for no other reason then she wanted to venture out and try new roles. She did however, express some fear on leaving the show.

"I've been given such a bountiful gift of the past ten years and, at this point in my life, I choose not to live my life from fear," Oh said. "The landscape for a working actor now is very worrisome. Having a shorter order of episodes is better for the writers and in the creative sense but being able to make a living and support a family? It's worse."

"So there have been moments where I have been talking with friends and fear creeps in. But as quickly as it does, I feel like I have built up a reserve to remind myself that I don't want to make decisions from that place because a lot in this town is based on fear, and I don't want to be a part of it anymore."

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