Fans were stunned recently when a former NCIS actor opened up about intense off-camera drama that nearly changed the direction of the show entirely. It turns out the tension wasn’t between two cast members, but centered around lead actor Mark Harmon and the original creator, Donald P. Bellisario.

In 2007, Harmon reportedly grew increasingly frustrated by Bellisario’s notoriously chaotic management style—particularly the grueling 16-hour workdays and last-minute script deliveries that disrupted the cast and crew. Not long after Harmon raised concerns, Bellisario stepped down as showrunner, though he remained an executive producer. The change brought smoother production behind the scenes and allowed the show to continue thriving.

This clash wasn’t just a footnote; many insiders believe it was a turning point for the series. Bellisario’s departure could have destabilized NCIS, yet the show emerged stronger, eventually becoming one of the longest-running and most successful dramas on television.

Over the years, other rumors of tension have surfaced as well, including rivalries between cast members as the series evolved. While most of these conflicts stayed behind closed doors, fans agree that the ability of the cast and crew to overcome them has been key to NCIS remaining a television powerhouse for over two decades.