On NCIS, "Abby Sciuto" and "Leroy Gibbs" formed a well-coordinated team. But what happened behind the scenes between the actors is very surprising. In October 2017, Pauley Perrette announced her retirement from the series after almost 15 years.

Until now, the actress kept a low profile about the reasons behind her leaving the show. But now she has gone public and revealed some dark secrets about her former co-star Mark Harmon (69).

Pauley Perrete, Jaime Camil and Natasha Leggero in the new CBS sitcom Broke.

Pauley Perrette will soon star in a new sitcom!

'NCIS': "Abby" Is Returning To TV Soon

Pauley Perrette is afraid of Mark Harmon

For many years, Pauley Perrette's character "Abby" was considered an absolute fan favorite, which is why fans still hope that she might return to the show one day, like one of THE favorite characters did recently. However, a few days ago the actress went on a Twitter rant when she was once again asked about a possible NCIS comeback. She will never return to the NCIS set again and Mark Harmon is the reason.

Pauley Perrette didn't spare any details during her rant. So she wrote: "NO I AM NOT COMING BACK! EVER! I am terrified of Harmon and him attacking me. I have nightmares about it."

The reason for the arguments on set was apparently because of Mark Harmon's dog - a fighting dog breed, which is said to have attacked several crew members.

Mark Harmon: His dog attacked the crew

Pauley Perrette is heavily burdening her ex-colleague with photographs of evidence. The picture shows an unknown crew member with severe, stitched bite injuries in the eye area.

The actress writes that she has worked hard for safety on the set, which has caused dog owner Harmon to freak out. "You think I didn’t expect blow back? You got me wrong. THIS happened to my crew member and I fought like hell to keep it from happening again! To protect my crew! And then I was physically assaulted for saying NO!? and I lost my job." the actress wrote in a now-deleted Tweet.

Mark Harmon has yet to comment on Pauley Perrette's severe allegations.