Rule Number One

""If somebody you knew, whether they were a criminal or a window washer, constantly talked about "the rules", you would never want to hang out with this fuckin' nitwit, would you? You're washing the window and the fucker says, 'Rule #1. No streaks.' What an annoying dude. Get him away from me.""

- Vern, reviewing The Transporter

He's in a dangerous or uncomfortable situation with other people who are less experienced or trustworthy than him, and he wants to make some things seriously clear. So he bluntly declares a numbered list of "rules" for the situation. Beginning, of course, with Rule Number One, and following it with Rule Number Two, and so forth. The implication of setting out these rules, and providing a semblance of structure by numbering them, is that they are resolute and unquestionable, and that breaking these rules will lead to dire consequences.

Of course, the character could just be using this stock phrase rhetorically, and simply conveying advice or admonishments.

A recent version of this trope has become so popular that nowadays, 90% of these will be Stock Shout-Outs to Fight Club -- "Rule Number One of [X]: You do not talk about [X]" and/or "Rule Number One: [Y]. Rule Number Two: [Y]!"

There Are No Rules is a subversion.

The Thieves' Guild most often has each of its members adhere to certain numbered rules.

For the other Rule Number One, see Badass Grandpa.

Characters who live by The Rules are obviously on the Lawful side of Character Alignment, but there's nothing stopping them from being Lawful Good or Lawful Evil. In fact, expect the latter from the Obstructive Bureaucrat who can cite pretty much any Rule that justifies him/her not doing anything remotely reasonable or helpful.

Anime and Manga

 * There is to be no discrimination between humans and robots in the Eve no Jikan.

Comic Books

 * In an issue of Alan Moore's Wild CATS run, one of the MERCs says: "Rule number 1: Don't @#$%& us. There's no Rule number 2"

Film
"Mr. Miyagi: Aha... here are the Two Rules of Miyagi-Ryu Karate. Rule Number One: "Karate for defense only." Rule Number Two: "Always remember Rule Number One.""
 * "The first rule of Fight Club is - you do not talk about Fight Club."
 * "The second rule of Fight Club is - you do not talk about Fight Club." Just in case you were curious.
 * The Transporter: "Rule number one: Never change the deal." "Rule number two: No names." "Rule number three: Never open the package."
 * The Karate Kid Part II:

"Rule 1: Don't move too soon. Rule 2: If you choose to bluff, you must be prepared to have your bluff called. Rule 3: Duck."
 * Scream: Randy Meeks's rules to surviving a scary movie, with Rule Number One being, "you can never have sex".
 * Starship Troopers: "This is for all you new people: I only have one rule. Everyone fights. No one quits. You don't do your job, I'll shoot you myself. You get me?"
 * Ghostbusters: Don't cross the streams....
 * Twins: The rules of a crisis situation -

"Rule 1: Cardio.
 * Zombieland has Columbus' list of 32 rules for surviving the Zombie Apocalypse.

Rule 2: Double Tap.

Rule 3: Beware of bathrooms.

Rule 17: Don't be a hero."


 * Fluke: Rumbo (Samuel L. Jackson) delivers a variety of Rule Number Ones throughout the movie as a catch phrase.

Literature
"`Well, I sha'n't go, at any rate,' said Alice: `besides, that's not a regular rule: you invented it just now.' `It's the oldest rule in the book,' said the King. `Then it ought to be Number One,' said Alice."
 * In Dirk Gently's Holistic Detective Agency, Richard is breaking into his girlfriend's apartment when he receives a mysterious phone call describing "the rules of breaking into an apartment". Rule number one is "never answer the phone".
 * In Terry Pratchett's novel Thief of Time, Lu-Tze often reminds people about Rule One. Unfortunately for them, not everyone gets the message. Rule One is:
 * And then there's Rule Nineteen, which is "Never forget Rule One, and ask yourself why it was invented in the first place."
 * Matthew Stover's Caine has three rules. They really boil down to "I'm the boss and can kill you to maintain this authority", and serve more to operate as a coercive threat than as a code of behaviour. If he ever asks you "What's Rule Two?", then you, my friend, are in deep shit.
 * Richard Sharpe has three rules for the men who serve under him: 1) Don't get drunk without permission. 2) Don't steal unless it is from the enemy or you are starving. 3) When it is time to fight, fight like bastards.
 * Miles Vorkosigan's cousin Ivan, critiquing someone else's covert op that almost failed miserably: "You play games like that with the big boys, you'd better make damn sure you win, Miles says. Rule One. And there is no Rule Two."
 * In Alice in Wonderland, the King of Hearts reads out Rule Forty-two: "All persons more than a mile high to leave the court."

""I have two rules I follow," Saren explained. "The first is: never kill someone without a reason." "And the second?" Anderson asked, suspicious. "You can always find a reason to kill someone.""
 * From ''Mass Effect: Revelation":

Live Action TV
"First Rule of Acquisition: Once you have their money, you never give it back. 33rd Rule of Acquisition: It never hurts to suck up to the boss. 45th Rule of Acquisition: Expand or die. Unwritten Rule of Acquisition: When no appropriate rule applies, make one up."
 * Ferengi are immensely fond of quoting Rules of Acquisition.

"The Doctor: Do you fancy a quick trip around the twelve galaxies and then back to Perivale in time for tea? Ace: Ace! The Doctor: But, there are three rules. One: I'm in charge. Ace: Whatever you say, Professor. The Doctor: Two, I'm not the Professor, I'm the Doctor. Ace: Whatever you want. The Doctor: And the third... Well, I'll think up the third by the time we get back to Perivale."
 * Played with: the first Rule of Acquisition was presented as #162 - to create a demand for #1 through #161.
 * A complete list of the rules (canon and non-canon) can be found here.
 * Ensign Robin Lefler, who appeared in one episode of Star Trek: The Next Generation, "The Game", had "Lefler's Laws", a list of rules she made up for herself. She still uses them when she becomes a main character in Star Trek: New Frontier.
 * The Prime Directive is the Federation's Rule Number One.
 * Doctor Who, "Dragonfire": The Doctor welcomes a new companion:

"The Doctor: Rule One: Don't wander off."
 * In the Doctor Who New Adventures novel Set Piece Ace, seemingly left with no choice but to kill the Doctor to save the universe, flashes back to this conversation (and occasions when the Doctor had to make similar decisions) and decides that the third rule - her rule - is "No-one deserves to be sacrificed".
 * In the new series the following is said to companions, not that they ever listen:

"Col. Blake: "All I know is what they taught me at command school. There are certain rules about a war. And rule number one is young men die. And rule number two is, doctors can't change rule number one.""
 * River Song's personal Rule One is, "The Doctor lies." And it turns out, along with Rule 7: "Never run when you're scared", Rule 27: "Never knowingly be serious" and Rule 408: "You should always waste time when you don't have any. Time is not the boss of you".
 * In "Human Nature", the Doctor leaves a set of 23 numbered rules for Martha to follow while he's transformed into a human and unaware of his true identity. In actuality, there were only about five instructions in the script (as Martha fast-fowards through most of them), and David Tennant hilariously ad-libbed dialogue for the skipped parts as seen here.
 * Buffy the Vampire Slayer: "The first rule of Slaying: Don't die!"
 * Not that this rule isn't broken. On more than one occasion. By the same character.
 * NCIS: Gibbs' various rules, cited by the characters throughout the show. Recently revealed in a flashback to have been inspired by his future wife on the day they met. Kate and Ziva both requested that Gibbs write the rules down, only to be told that most of the rules are for day-to-day tasks. Rules in the forties however are reserved for emergencies.
 * TWO rules are apparently number one (and two rule number threes), likely due to an oversight on the part of the writers, although later confirmed to have been intentional. Recently, however, this was lampshaded when the female version of Gibbs from CGIS told McGee HER rule number one and suggested he write it down. McGee replies that rule number one has been taken, twice.
 * The reason there are two Rule Number Ones is one of them refers to Gibb's personal list inspired by his wife. The other one was inherited from Mike Franks, Gibbs' boss when he first became an NCIS Agent. Mike Franks told Gibbs that he didn't need a list of rules, he only needed "Three Golden Rules". It has not been revealed which of the rules are Gibbs' and which are Franks, nor has the second Rule Number 2.
 * RoboCop: The Series had an episode featuring Murphy's old partner, a cop with a set of rules amounting to "no vigilantism". When said cop was brainwashed, Robo brought him back by making him say his rules. A minute later, he was killed with a rocket launcher.
 * Unproduced 2008 TV pilot Captain Cook's Extraordinary Atlas (available here) mentions three rules that were followed by Captain James Cook when exploring the more fantastic areas of the Earth, and that were supposed to be followed by subsequent "navigators".
 * In one of the most well-known M*A*S*H episodes ("Sometimes You Hear the Bullet" - the show's first Wham! Episode and its Growing the Beard moment), Henry Blake tells Hawkeye:

"Robot Club Leader: Gentlemen, welcome to Robot Club. The first rule of Robot Club is, you do not talk about about Robot Club. The second rule of Robot Club is, YOU DO NOT TALK ABOUT Ro? wait, I? got that wrong. [Unfolding a crumpled up piece of paper and pushing up his glasses] The second rule is, no smoking. Tim: Why aren't we allowed to smoke? Mike: Shh, we're not allowed to talk about it."
 * In Red Dwarf, Kryten would often quote the Space Corps Directives, with a number each time. Rimmer would try to do the same, but get the numbers wrong; for example, quoting Directive 34124, which Kryten informed him was "No officer with false teeth should attempt oral sex in zero gravity."
 * Fight Club is parodied in the Robot Club episode of Spaced:

""Rule one - no pooftahs. Rule two, no member of the faculty is to maltreat the Abbos in any way whatsoever - if there's anybody watching. Rule three - no pooftahs. Rule four - I don't want to catch anyone not drinking in their room after lights out. Rule five - no pooftahs. Rule six - There Is No Rule Six! Rule seven - no pooftahs. That concludes the reading of the rules, Bruce.""
 * Monty Python's Flying Circus gives us the faculty rules of the Philosophy Department of the University of Woolamaloo:

"Barney: "Now, here at the Rock we have two basic rules. Memorize them, so that you can say them in your sleep. The first rule is: Obey all rules. Secondly, do not write on the walls, as it takes a lot of work to erase writing off of walls.""
 * In The Andy Griffith Show episode "The Big House", Barney Fife lays down the law for two new inmates at the jail:


 * The same gag appears in Porridge, only with the rules in the opposite order.
 * Harry taught Dexter a code to control his psychopathic tendencies. It had whole sections to make sure he only went after bad guys, but as he tells  toward the end of season 2 in response to the suggesting that he turn himself in, Rule Number One was always Don't Get Caught.
 * According to Harry, that was the point of the whole endeavor, keeping Dexter alive; thus it's the first rule.
 * In The IT Crowd, "the first rule of Street Countdown... is that you really must try and tell as many people as possible about it. It's a rather fun game and the more people you tell about it the better."

Video Games
"Don Weaso: Rule number one: My way, or 'he's a dead mother(bleep)' way."
 * Conkers Bad Fur Day: In the 'Heist' multiplayer:

"Aria T'Loak: Omega has no titled ruler and only one rule; Don't fuck with Aria."
 * Mass Effect 2: While on Omega:

Web Comics
"Captain Tagon: I didn't know you could do that.
 * Order of the Stick: here.
 * Schlock Mercenary has the Seventy Maxims of Maximally Effective Mercenaries. Rule one: Pillage, then burn.
 *  (ship computer column turns into lots of smoke and small pieces)
 * The first rule of A.I. kill switches is "don't talk about the kill switch"."

"Rule #3: We are in the business of solving problems for our clients. Corollary: Creating problems for our clients creates business."
 * Charlie's Rules for his Archons in Erfworld include:

"Rule #19: Charlie's rules need to be bent sometimes. Corollary: Most of the time Charlie's rules don't need to be bent."
 * ...but there's also an all-purpose loophole:

"Ken: First, in battle yer either killin' or dyin'. So whatever you do, don't ever stop not dying. Second, we don't have time for stupid rules. So stop just standing around like a buncha idiots, and start beat'n the crap outta each other!"
 * Precocious has so far subjected the kids to two numbered rules.
 * Rule #1:
 * Rule #4:
 * Xkcd: The first rule of the tautology club is the first rule of the tautology club.
 * The first rule of talking to me about movies is do NOT talk about Fight Club.
 * No Need for Bushido has "Ken's rules to fight'n":

Web Original
"Carapar: Rule number one: don't annoy the giant, tentacled monster!"
 * From Bionicle: Federation of Fear:

Western Animation
"Genie: Rule number one: I can't kill anybody, so don't ask. Rule number two: I can't make anybody fall in love. Mwa! You little punim there. Rule number three: I can't bring people back from the dead. It's not a pretty picture. I don't like doing it!"
 * Aladdin's Genie.

"Phil: Rule number six: When rescuing a damsel, always handle with care."
 * Phil from Hercules has a whole list of rules for being a hero.

"Yeti: Rule number one out here: Always... no, never go out in a blizzard."
 * Monsters, Inc.:


 * On Family Guy, Peter recounts the story of his ancestor, Moses Griffin, who led the Hebrews out of Egypt. His Rule Number One: Shut the hell up.
 * In Adventures of the Galaxy Rangers, Doc appears to have a list of reasons explaining why he is sorry he became a Galaxy Ranger. He only seems to quote them when Goose is driving.

Real Life
"Rule #1: The customer is always right. Rule #2: If the customer is ever wrong, see Rule #1."
 * The Sicilian Mafia.
 * The 36 Oaths of the Triads.
 * The grocery store Stu Leonard's has a sign up near the entrance that reads as follows:


 * Ah, so that's who we have to blame for that.
 * Rule number one on the streets: No Snitching.
 * Rule Number One of Holes: When you find yourself in one, stop digging.

Wikis, websites and the Internet in general

 * Rules of Anime.
 * Rule 34, one of the Rules of the Internet.
 * As mentioned in the Ferengi Rules of Acquisition example, above, 34 was the first one created, the rest followed afterward.
 * TV Tropes Wiki has Three Rules of Three.
 * First rule of furry fandom: You don't recover