It’s no secret that Shonda Rhymes’ Grey’s Anatomy is the longest-running medical drama TV series of all time. Now, after 19 seasons, fans of the show have seen it all. From a bunch of major character deaths to the most bizarre medical cases.

But if there’s one thing Grey’s Anatomy is well-known is the rumors about how hard it is to actually work on the show, which is why so many stars have had to leave the show. Sandra Oh, for example, admitted that filming Grey’s Anatomy was physically draining. On the other hand, many other actors have been fired from the show for their allegedly problematic behavior, like Katherine Heigl and Patrick Dempsey.

Recently, Dempsey cleared the rumors about him terrorizing the Grey’s Anatomy set, which supposedly led to his character being written off in the show’s eleventh season.

Related: From Alex To Lexie: Here's What These Fan-Favorite Grey's Anatomy Stars Have Done Since Their Exit

Patrick Dempsey Was Only Given The Role Of Derek Shepard Because Another Famous Actor Didn’t Want It

Patrick Dempsey’s acting career started back in the 80s. According to IMDb, his first gig was a small part in the drama Heaven Help Us (1985). Between the 80s and the early 2000s, Dempsey landed leading roles in numerous romantic movies such as Can't Buy Me Love (1987), Sweet Home Alabama (2002), Disney’s Enchanted (2007), Made of Honor (2008), and Valentine's Day (2010).

In 2005, Dempsey made his debut as neurosurgeon Derek Shepherd in ABC’s Grey’s Anatomy. Despite playing this character so well for 11 seasons, turns out that Dempsey wasn’t the first option for the role. He only got cast after Rob Lowe declined to play this beloved character.

Derek Shepherd, also known as McDreamy, was Meredith Grey’s (Ellen Pompeo) romantic love interest throughout the show’s first eleven seasons. Dempsey’s acting soon made this character become one of the fan favorites. That’s why fans were devastated to see this major character get killed off the show in the Grey’s Anatomy season 11 finale.

Related: Is The Most Heartbreaking 'Grey's Anatomy' Episode The One When Derek Shepherd Dies?

And despite claims that Dempsey got written out the show because of his problematic behavior on set, the actor returned to Grey’s Anatomy for the show’s 17th season. Although he was a product of Meredith's dreams while fighting COVID-19, Dempsey told Good Morning America that he was grateful for the chance to play this character once again.

Patrick Dempsey Claims That He Decided To Leave The Show Because It Was Too Time-Consuming

Fans thought that killing Derek Shepherd had been a rash decision. But, in reality, Dempsey had been planning to leave the series for a long time.

In 2016, the actor told People that his reasoning for quitting Grey’s Anatomy had to do with how time-consuming it was to film the show.

“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,” he explained.

At the time following his departure, it seemed that killing Derek Shepherd had been a joint decision between Dempsey and the show’s creator, Shonda Rhymes. But Lynette Rice's unauthorized book about what really happened behind the scenes of this medical drama show has made fans believe that there were other reasons to get Dempsey off the show.

Related: It Turns Out This Fan Theory About Patrick Dempsey's 'Grey's Anatomy' Exit Was True

Dempsey’s Behavior In The Grey’s Anatomy Set Could Have Been The Real Reason Behind His Departure

In How to Save a Life: The Inside Story of Grey’s Anatomy, Lynette Rice revealed that both cast members and producers weren’t happy with Patrick Dempsey’s problematic behavior on set. It seems that Dempsey’s behavior was what ultimately led to the decision to kill his character, Derek Shepherd.

Apparently, Dempsey once got in a fight with Isaiah Washington, who played Dr. Preston Burke in the show’s early seasons. And, in her book, Lynette Rice revealed this wasn’t the only cast member Dempsey got into altercations with. "There was talk of Dempsey’s diva-like fits and tension between him and Pompeo," she wrote.

Moreover, in How to Save a Life, executive producer James D. Parriott talks about alleged "HR issues" with Dempsey, claiming that the actor was constantly terrorizing the set. "He had this hold on the set where he knew he could stop production and scare people. The network and studio came down and we had sessions with them. I think he was just done with the show. He didn’t like the inconvenience of coming in every day and working. He and Shonda were at each other’s throats”, Parriott claimed.

Although Patrick Dempsey hasn’t opened up about what really happened on the set of Grey’s Anatomy, it seems that the actor doesn’t seem to hold any grudges. After all, he came back to the show in 2021 for four episodes.