NCIS: Gibbs' Rule 45 Explained

Throughout his run in the "NCIS" franchise, Special Agent Leroy Jethro Gibbs (Mark Harmon) has followed a code — a set of rules, if you will. These self-imposed edicts inform both his personal and professional life, and he has imparted some of that wisdom on his colleagues to great effect. Mind you, Gibbs hasn't shared every single one of his rules (part of the fun of watching "NCIS" is waiting for new ones to be revealed), but there are at least 91 of them. What is certain, though, is Gibbs has shared and lived by Rule 45, which is a simple one: clean your mess. So, what does this rule mean exactly?

On one hand, it can be interpreted in the literal sense — cleaning your dishes, picking up your litter, etc. However, Gibbs' meaning is more complex, as it pertains to covering up loose ends in regard to investigations, personal issues, or — as Gibbs can relate to — acts of bloody vengeance against Mexican Cartel members. In simple terms, Gibbs believes that everyone is responsible for fixing their own mistakes, and they must be willing to take accountability for their actions.

Rule 45 is one that can apply to all walks of life, but when did Gibbs officially add it to the book in CBS' hit procedural? To answer that question, we must revisit "NCIS" season 7.

The deaths of Leroy Gibbs' wife and daughter on "NCIS" really motivated him to live by a code. His late spouse believed that everyone should follow a set of rules, and while he co-opted this belief system during her lifetime, it became more important to him following her demise. The rules also serve Gibbs and his colleagues well, but it took a while for everyone to learn about the 45th. The genesis of the rule can be traced back to season 3's "Hiatus (Part II)," where it's referred to as tying up loose ends — but it wasn't confirmed as an official mantra Gibbs swears by until later seasons.

Rule 45 becomes official in "NCIS" season 7's "Rule Fifty-One" episode, which sees Gibbs get into a spot of bother with the Reynosa Cartel, aka the family of the criminal who murdered his wife and daughter. Gibbs responded to the crime by killing their assassin in cold blood, leaving a traceable bullet inside his skull — a loose end if there ever was one, even though it was intentional at the time. In season 7, the case is almost reopened and risks ruining Gibbs' career, and the Cartel threatens to kill his remaining loved ones if he doesn't play by their rules. Talk about having a real mess to clean up, right?

Introducing Rule 45 in an episode where Gibbs almost loses everything is fitting, and "Rule Fifty-One" illustrates that poor decisions don't just affect the person who makes them in the first place. What's more, Rule 45 continues to inform the show's storytelling — even though Mark Harmon exited "NCIS" in 2021, leaving Gibbs free to spend the rest of his days fishing in Alaska.

The beauty of rules is that anyone can follow them, and many remain influential long after their originators are out of the picture (see: The 10 Commandments, the U.S. Constitution, etc). The creators of "NCIS" understand this sentiment, as Leroy Gibbs' Rule 45 informs the storyline of the season 22 episode "Irreconcilable Differences" in a big way.

In this one, Agent Timothy McGee (Sean Murray) is out to expose a crooked, high-ranking NCIS official for being the criminal he is. Of course, this mission is easier said than done, as the top dogs don't go down without a fight. McGee is arrested for harassing his target, forcing him to make a break for it and solve the case off the grid. The system is against him, but McGee leaves a note that states "Rule 45" for his trusted colleagues to find, essentially informing them that he plans to fix the mess he created.

This episode highlights Gibbs' everlasting influence on his old colleagues and the work they do, all while emphasizing the rules' usefulness as a storytelling device for the show's creators. Gibbs' Rules are part of the fabric of "NCIS," and no. 45 has inspired some great stories about the agents going above and beyond to ensure everything is right with the world.