NCIS, the popular procedural drama, recently celebrated its 450th episode in its 20th season. In contrast to the previous milestone episode, which explored the backstory of Gibbs and Ducky, this one followed the show's regular format. However, despite its lack of fanfare, it once again showcased the show's legacy of blending standalone investigations with glimpses into the personal lives of its agents.

When looking back at all the milestones the series has reached so far, there have been some standout episodes that have left a lasting impression on viewers. Starting from the least memorable and working our way up:

Episode 450: "Unusual Suspects"

In this milestone episode, the team solves another case-of-the-week while Agent Parker deals with his father moving in with him. While this episode didn't stand out as a significant milestone, it exemplified the show's ability to seamlessly integrate personal storylines into its procedural format.

Episode 50: "Silver War"

This episode marked Ziva's official introduction as the Mossad liaison to the team. Apart from that, it didn't have much else going for it in terms of memorable moments. Considering it was just the 50th episode, it's not surprising that it didn't make a lasting impact.

Episode 250: "Dressed to Kill"

This milestone delved into Tony's family history, with Robert Wagner reprising his role as Tony's father. While it was entertaining to see Senior involved in the case, it didn't stand out as particularly special compared to other milestone episodes.

Episode 350: "Sight Unseen"

This episode featured the team working with a blind witness to solve a case, emphasizing the partnership between Torres and the witness. Their dynamic made this episode noteworthy and deserving of a rewatch.

Episode 100: "Chimera"

Gibbs and the team leave the office to investigate aboard a top-secret naval research ship.

Episode 150: "Flesh and Blood"

Fans finally meet Tony's father, Senior, in this milestone episode. It successfully showed Tony's complex relationship with his father, which served as a blueprint for future episodes centered around DiNozzo.

Episode 400: "Everything Starts Somewhere"

This milestone episode revealed the first case that brought Gibbs and Ducky together. While the case itself wasn't particularly memorable, the focus on their relationship in both past and present timelines made it a highlight of the series.

Episode 200: "Life Before His Eyes"

This episode explored the "what if" concept, imagining different outcomes for past events. It posed questions fans have often asked themselves and delivered heartbreak, regardless of the choices made.

Episode 300: "Scope"

Considered one of the best episodes of the series, the 300th milestone struck a perfect balance. It featured Gibbs connecting with Aaron Davis, played by Taye Diggs, who suffered from PTSS. The personal moments between the characters, a powerful rendition of "Hallelujah," and McGee's proposal to Delilah made this episode stand out as the top milestone.

As NCIS continues its successful run, these milestone episodes serve as reminders of the show's enduring popularity and ability to mix engaging cases with compelling character development.