NCIS Special Agent Leroy Jethro Gibbs, portrayed for over a decade by the incomparable Mark Harmon, lives life by a set of rules. Most of which be abides by.
Gibbs' rules may be fluid, ever-changing and incomplete (many of them have yet to be revealed), but fans of the CBS drama know they've been a staple since Season 1.
The "40s" are said to be especially important, while the list was believed to comprise about 50 rules, with a 51st added with major impact in the Season 7 finale.
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Rule #1: Never let suspects stay together. (Season 1 Episode 1, Mike Franks)
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Never let suspects stay together. (Season 1 Episode 1, Mike Franks)
Rule #1
1.
Rule #1 (Mike) Never let suspects stay together. (Season 1 Episode 1, Mike Franks)
Never screw over your partner. (Season 4, Episode 14, Gibbs)
Rule #1
2.
Rule #1 (Gibbs) Never screw over your partner. (Season 4, Episode 14, Gibbs)
Always wear gloves at a crime scene. (Season 1, Episode 1, Mike Franks)
Rule #2
3.
Rule #2 Always wear gloves at a crime scene. (Season 1, Episode 1, Mike Franks)
Don't believe what you're told. Double check. (Season 1, Episode 1, Mike Franks)
Rule #3
4.
Rule #3 (Mike) Don't believe what you're told. Double check. (Season 1, Episode 1, Mike Franks)
Never be unreachable. (Season 3, Episode 13, Gibbs)
Rule #3
5.
Rule #3 (Gibbs) Never be unreachable. (Season 3, Episode 13, Gibbs)
The best way to keep a secret? Keep it to yourself. Second best? Tell one other person, if you must. There is no third best. (Season 4, Episode 11)
Rule #4
6.
Rule #4 The best way to keep a secret? Keep it to yourself. Second best? Tell one other person, if you must. There is no third best. (Season 4,...
You don't waste good. (Season 8, Episode 22)
Rule #5
7.
Rule #5 You don't waste good. (Season 8, Episode 22)
Never apologize. (Season 7, Episode 12, but referenced previous times without a number attached)
Rule #6
8.
Rule #6 Never apologize. (Season 7, Episode 12, but referenced previous times without a number attached)
Always be specific when you lie. (Season 1, Episode 23)
Rule #7
9.
Rule #7 Always be specific when you lie. (Season 1, Episode 23)
Never take anything for granted. (Season 3, Episode 10)
Rule #8
10.
Rule #8 Never take anything for granted. (Season 3, Episode 10)
Never assume. (Season 9, Episode 21)
Rule #8
11.
Rule #8 (Alternate Version) Never assume. (Season 9, Episode 21)
Never go anywhere without a knife. (Season 1, Episode 13)
Rule #9
12.
Rule #9 Never go anywhere without a knife. (Season 1, Episode 13)
Never get personally involved on a case. (Season 7, Episode 21)
Rule #10
13.
Rule #10 Never get personally involved on a case. (Season 7, Episode 21)
When the job is done, walk away. (Season 6, Episode 24)
Rule #11
14.
Rule #11 When the job is done, walk away. (Season 6, Episode 24)
Never date a coworker. (Season 1, Episode 15, and referenced on other occasions)
Rule #12
15.
Rule #12 Never date a coworker. (Season 1, Episode 15, and referenced on other occasions)
Never, ever involve a lawyer. (Season 6, Episode 7; Gibbs is said to have other rules involving lawyers, but according to Tony, this is the "umbrella" one)
Rule #13
16.
Rule #13 Never, ever involve a lawyer. (Season 6, Episode 7; Gibbs is said to have other rules involving lawyers, but according to Tony, this is...
Never leave behind loose ends. (Season 3, Episode 24)
Rule #45
17.
"Never leave behind loose ends." Never leave behind loose ends. (Season 3, Episode 24)
Bend the line, don't break it. (Season 11, Episode 4)
Rule #14
18.
Rule #14 Bend the line, don't break it. (Season 11, Episode 4)
Always work as a team. (Season 5, Episode 5)
Rule #15
19.
Rule #15 Always work as a team. (Season 5, Episode 5)
If someone thinks they have the upper-hand, break it. (Season 8, Episode 24)
Rule #16
20.
Rule #16 If someone thinks they have the upper-hand, break it. (Season 8, Episode 24)
It's better to seek forgiveness than ask permission. (Season 3, Episode 4)
Rule #18
21.
Rule #18 It's better to seek forgiveness than ask permission. (Season 3, Episode 4)
Never, ever bother Gibbs in interrogation. (Season 4, Episode 10)
Rule #22
22.
Rule #22 Never, ever bother Gibbs in interrogation. (Season 4, Episode 10)
Never mess with a Marine's coffee if you want to live. (Season 2, Episode 9)
Rule #23
23.
Rule #23 Never mess with a Marine's coffee if you want to live. (Season 2, Episode 9)
Rule #27: Two ways to follow: First way, they never notice you, Second way, they only notice you. (Season 7, Episode 15)
24.
Rule #27 Rule #27: Two ways to follow: First way, they never notice you, Second way, they only notice you. (Season 7, Episode 15)
Always watch the watchers. (Season 8, Episode 22)
Rule #35
25.
Rule #35 Always watch the watchers. (Season 8, Episode 22)
If feels like you're being played, you probably are. (Season 9, Episode 1)
Rule #36
26.
Rule #36 If feels like you're being played, you probably are. (Season 9, Episode 1)
Your case, your lead. (Season 6, Episode 16; Season 10, Episode 3)
Rule #38
27.
Rule #38 Your case, your lead. (Season 6, Episode 16; Season 10, Episode 3)
There is no such thing as a small world. (Season 10, Episode 14)
Rule #39A
28.
Rule #39 There is no such thing as a small world. (Season 10, Episode 14)
There is no such thing as coincidence. (Season 7, Episode 21)
Rule #39
29.
Rule #39 (Alternate Version) There is no such thing as coincidence. (Season 7, Episode 21)
If it seems someone is out to get you, they are. (Season 7, Episode 22)
Rule #40
30.
Rule #40 If it seems someone is out to get you, they are. (Season 7, Episode 22)
Never accept an apology from someone who just sucker punched you. (Season 9, Episode 16)
Rule #42
31.
Rule #42 Never accept an apology from someone who just sucker punched you. (Season 9, Episode 16)
First things first. Hide the women and children. (Season 7, Episode 23)
Rule #44
32.
Rule #44 First things first. Hide the women and children. (Season 7, Episode 23)
Clean up your own mess. (Season 7, Episode 24)
Rule #45
33.
Rule #45 Clean up your own mess. (Season 7, Episode 24)
Sometimes you're wrong. (Season 7, Episode 24, titled "Rule Fifty-One")
Rule #51
34.
Rule #51 Sometimes you're wrong. (Season 7, Episode 24, titled "Rule Fifty-One")
I know rule 62 is to always give people space when they get off the elevator but this is really important and I don't want to waste any time.
Abby
35.
Rule #62 Always give people space when they get off the elevator. (Season 11, Episode 13, as revealed by Abby)
Never trust a woman who doesn't trust her man. (Season 9, Episode 7)
Rule #69
36.
Rule #69 Never trust a woman who doesn't trust her man. (Season 9, Episode 7)
You do what you have to for family.
Unwritten Rule
37.
The Unwritten One You do what you have to for family.
However, a 69th rule was dropped out of nowhere in Season 9, and #62 was revealed in a throwaway line in the most recent hour of NCIS Season 11 ... so who knows.
There have been examples of Gibbs and his team breaking them (3, 6 and 12 come to mind), and there are two different rules for #1 and #3, anomalies attributed to Mike Franks.
Rules 1-3 for Gibbs and his late mentor are therefore distinct; Gibbs' #2 hasn't been revealed … we don't think. Other NCIS team members have revealed their own rules as well.
Which rules are your favorites? What do you think some of his yet-to-be-revealed pearls of wisdom might be? Did we miss any or get any of them wrong?
Scroll through TV Fanatic's Gibbs Rules slideshow above and and share your thoughts and comments. We'll make the additions and corrections as needed!