A new book revealed Patrick Dempsey's last days on "Grey's Anatomy" and how he reportedly terrorized the set of the series.

"Grey's Anatomy" executive producer James D. Parriott recently published a book where he touched Dempsey's issues during his stay.

The Hollywood Reporter shared a critical part of the book, revealing how the "HR issues" on Dempsey led to his character getting killed off in 2015.

"There were HR issues. It wasn't sexual in any way. He sort of was terrorizing the set, Parriot - one of the book's 80-plus sources - said. 'Some cast members had all sorts of PTSD with him," he said.

Since Dempsey became one of the biggest stars of the show, he managed to continue his stint until the end of Season 11. His character, Dr. Derek Shepherd, famously became Meredith Grey's love interest, causing him to gain more popularity.

In fact, the show's creator, Shonda Rhimes, reportedly saw him as a perfect man after becoming the favorite leading man. Writer Jeannine Renshaw also recalled him as someone who is a sweetheart.

Despite the creators' positive comments about him, the negative ones outshined them after the actor continuously scared people on the set.

How Patrick Dempsey Terrorized "Grey's Anatomy" Set

Parriott shared more details about the "HR issues" in question and shared how he had too much say over the set's production.

Per the executive producer, the 55-year-old actor had the absurd power to stop the production and scare people. As the issue repeatedly occurred, the network and the studio finally sat down with him and decided to kill off his character.

"He didn't like the inconvenience of coming in every day and working. He and Shonda were at each other's throats," he went on.

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Renshaw noted that the "Grey's Anatomy" conflict later caused cracks in his relationship with Ellen Pompeo. The on-screen wife reportedly felt frustrated with the actor as he was not working as much anymore.

Pompeo wanted everything and everyone to be treated fairly. Thus, she could not take it whenever Dempsey reasoned out that he had been part of the show for too long.

After multiple incidents, Shonda witnessed what was wrong with Dempsey and reached the final straw. Although he could record his parts away from Pompeo and others, the network ultimately snatched his chance and decided not to bring him back.

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