Pauley Perrette shocked NCIS fans when she announced her departure from the hit crime show after 16 seasons. Although Perrette did not say why she decided to leave the series, an inside source claims that the NCIS star left because she felt threatened by Mark Harmon’s savage pit bull. Perrette Felt Threatened On The Set Of NCIS A source told Radar Online that Perrette did not feel safe whenever Harmon’s dog was on set. The actor rescued the pit bull, named Dave, a few years ago and frequently brought him on the set of NCIS. In the fall of 2016, the dog sent a crew member to the hospital after a vicious attack. The bite was so bad that doctors gave the crew member 16 stitches to close the wound. Shortly after the incident, inside sources claimed that the man was playing rough with the dog at the time of the attack. With the blame shifting to the crew member, Harmon continued to bring the pooch on set.