[[caption-width-right:320:''"..You'll find you'll need us, 'cause there's no one else to call..."'']]

The 1980s version of ''Series/TheModSquad'', with a somewhat more believable premise. The series lasted from April, 1987 to April, 1991, with a total of 103 episodes in five seasons.

''21 Jump Street'' was the Creator/{{Fox}} Network's first drama, and aired on its premiere night along with sitcoms ''Series/MarriedWithChildren'', ''The Tracey Ullman Show'', ''Duet'' and ''Mr President''.

Here, it's about a special undercover police unit in an [[CityWithNoName unnamed American city]], where young-looking police officers infiltrate schools to investigate youth-related crimes.

The series made Creator/JohnnyDepp a star, but a TeenIdol was the last thing he wanted to be. As such, he quit at his first opportunity, which made the show JumpTheShark at that moment.

A very well received [[Film/TwentyOneJumpStreet film "sequel"]] (in a completely different genre) has been released, starring Creator/JonahHill (who also co-wrote the script), Creator/ChanningTatum, [[TheUnitedStatesOfTara Brie Larson]], and Music/IceCube. Creator/JohnnyDepp and Peter [=DeLuise=] appear in cameos as their original-series characters, Tom Hanson and Doug Penhall. Holly Robinson Peete also returned as Judy Hoffs, in a slightly more substantial role. Due to the drastic difference in tone, the movie is not necessarily recommended for fans of the series.
!!This series provides examples of:
* AdultsDressedAsChildren: More adults dressed as teenagers; the whole premise of the show is young looking police officers going undercover in high schools. Decades later, Depp would poke fun at the "fascist" nature of this premise.
* AmbiguousEnding: Due to the show's attempts to confront such difficult issues as drug use and criminal behavior in high schools somewhat realistically, episodes often end this way, sometimes qualifying for a DownerEnding if a student they're trying to protect dies or goes to jail, but leaving the viewer with the question of what to do about the tragic circumstances that led to it.
* ArtisticLicenseHistory: Due to a slightly awkward RetCon, Ioki is hiding the fact that he is Vietnamese, supposedly to avoid the ire of colleagues who may have fought in the Vietnam war. The strange thing is, Ioki would almost certainly be from (the former) South Vietnam, who were America's allies. (And even if he was from North Vietnam, his colleagues wouldn't know that.)
** Unless their potential discrimination were based on resentment of being in the war instead of hatred for the enemy.
* AssholeVictim: The ShockJock whose car gets blown up in "Next Victim". Due to his hateful and racist ranting, the team is none too happy about having to look for the person who did it.
* BadassLongCoat: Booker wears these on occasion, when not sporting a [[HellBentForLeather leather jacket.]]
* BerserkButton: Hanson ''reaaally'' hates it when people make fun of how young he looks.
* BowlingForRatings: Hanson is an avid bowler.
* BreatherEpisode: "Chapel of Love", in which the guys reminisce about bad dates over a poker game on Valentine's Day, could be considered this, coming right after a VerySpecialEpisode about a teenager with AIDS.
* CaliforniaDoubling: Though supposedly set in the U.S., the fact that ''21 Jump Street'' is shot in Canada is made by the fact that the extras/bit parts were hired locally and thus do decidedly non-US things like say "grade 3" instead of "3rd grade" and write graffiti with words ending in "-our" instead of "-or".
** The only slightly blurred "Beautiful British Columbia" license plates are also a dead giveaway. And the bus route prominently displayed in the credits: Hastings.
* TheChick: Judy Hoffs. However, she is the only one of officers to make Detective, and is depicted as being an intelligent, well rounded member of the cast. Her status as the chick comes from her tendency to rely on her feelings about the suspect, which often are proven wrong. Also, she tends to be addressed by first name more often than the other officers.
* ClumsyCopyrightCensorship: The American [=DVDs=] suffer from this - while the licensed music wasn't the WHOLE draw of the show, it was an important part of the atmosphere, and lyrics were often used to communicate plot, which makes chunks of some DVD episodes make very little sense now that they're backed by nothing but elevator music. The [=DVDs=] still sold enough to finish the show, possibly because there weren't many bootlegs in circulation. Uploads of the show now are almost always from this butchered version, even though the full versions do exist (see the Trivia page).
* ComingOfAgeStory: Played straight for some of the rebellious teens featured. Subverted for Hanson, who spent his youth as an uptight Republican and doesn't go through his rebellious phase until after joining the Jump Street division.
* CompulsorySchoolAge: The cops are still adult age, but they look like high schoolers, so they have to go to high school to fight crime that happens in/around high school.
* CrimeAndPunishmentSeries
* DaChief: After Capt. Jenko is killed off, Capt. Fuller takes over and makes it very clear from the beginning that he means business and giving him any lip is a ''bad'' idea.
* DirtyHarriet: Judy joined the Jump Street program because it was the only way she'd be able to get any ''other'' type of assignment. Of course, this didn't mean that she didn't ''still'' get just such an assignment occasionally.
* DisguisedInDrag: Both Hanson and Ioki had to do this for undercover assignments.
* DoItYourselfThemeTune: The theme tune was performed by Holly Robinson who played Officer Judy Hoffs on the show (with the "JUMP!" shout provided by Johnny Depp and Peter [=DeLuise=]).
** Incidentally, this is one of the few Creator/StephenJCannell shows where the theme tune was ''not'' written by Mike Post (see also ''Hawkeye'' ([[MarvelCinematicUniverse not that one]]), ''Cobra'', ''Street Justice'' and ''Missing Persons'').
* DroppedABridgeOnHim: Captain Jenko, WeHardlyKnewYe.
* DudeNotFunny: In "Best Years of Our Lives", this is pretty much everyone's in-universe reaction to Penhall when he starts telling incredibly crass jokes about suicide as a coping mechanism to deal with a student killing himself (and, as it turns out, his own mother doing the same back when he was just six).
* EightiesHair: A huge offender.
* FanSequel: ''[[http://www.youtube.com/watch?v=_XspU4ZxHkw 21 Jump Street Rangers]]'', which takes place years after the original team's adventures. (The series also adapts ''Series/TomicaHeroRescueForce'' for added points.)
* GoshDangItToHeck : Happens frequently. "Good gaul-darn riddance!"
* HenpeckedHusband: Despite not actually being married, Penhall gets a bad case of this when Dorothy rather abruptly decides to not only get back together with him, but also to move in with him. Cue every nagging housewife cliche the writers can think of.
* HoldTheUnsolicitedIngredient: The episode "Gotta Finish the Riff"
-->'''Reginald Brooks:''' [ordering pizza for his hostages] I want 10 with sausage, 10 with pepperonis. And no anchovies. I see one anchovy and I kill the librarian
* ImGoingToHellForThis: In "Chapel of Love", after telling a story about the time he had an affair with his partner back in the 70s and getting ridiculed by the other guys got it, Captain Fuller points out that they're all going to hell anyway for playing poker in a church.
* ManicPixieDreamgirl: An episode featuring a girl named Quincy, who sort of positions herself as this, dragging the straight-laced Hanson around and trying to convince him to "lighten up". Of course, her idea of fun is crime sprees and potentially-fatal thrill-seeking. She terrifies him, and ends up [[spoiler: shot to death by security guards while robbing a house.]]
* MaybeMagicMaybeMundane: The 'psychic' girl in the Halloween episode. She sees/draws things that she shouldn't have any way to know, but she's not infallible either. Psychic, or lucky guess?
* MrFanservice: Young Johnny Depp.
* MsFanservice: Young Holly Robinson. There's an in-story reason for it sometimes, when they want her to pose as a "bad girl" and/or [[DistractedByTheSexy distract a perp]].
* NewAgeRetroHippie: Captain Jenko, an aging hippie who, in the first episode, has to teach Hanson how to act like a bad seed.
* OlderThanTheyLook: The show was entirely based around the premise of cops who looked young enough that they could go undercover as high school students.
** Which was pretty silly, and only sorta worked because of DawsonCasting. The actors standing next to ACTUAL high-schoolers would've looked hopelessly out of place.
*** Not silly considering many programs were based on cops passing as high school students.
* OrphanedPunchline: The third season premiere ends with a joke of the "Several racial stereotypes walk into a bar" variety being told by Booker to Hanson. We never hear the punchline, which fits the overall AmbiguousEnding concerning whether Booker is actually racist or was just playing the role for a case he and Hanson had worked on together.
* PoliceAreUseless: The opinion of the Street Rangers from season three.
* RedOniBlueOni: Penhall and Hanson, respectively.
* RewindReplayRepeat: In one episode, Officer Tom Hanson witnesses his girlfriend being shot in a convenience store robbery and feels guilty that he was unable to stop him. He spends his days watching the surveillance camera tape, replaying the same moment over and over, being obsessed over how much time it would take for him to have been able to stop the murderer.
* PopularHistory: The show stands as a good example of what the 80's were actually like.
* SadClown: Penhall.
* SchoolyardBullyAllGrownUp:
** In the episode ''Woolly Bullies'', the main characters recount the bullies who have plagued them in their youth. When Doug Penhall recounts his particularly bitter memories of such a tormentor, a friend suggests he seek the bully out and confront him. However, when Penhall does just that by finding the bully's current home, he learns that the bully is now a pathetic unemployed loser with an unhappy marriage to a shrewish wife. Delighted at this turn of events, Penhall decides not to speak to him and returns home quietly gloating how he got the classic best revenge by living well.
** He even suffered a case of ThrewMyBikeOnTheRoof.
* ShooOutTheNewGuy: Booker, who is [[CoolPeopleRebelAgainstAuthority totally rad]] and [[JerkWithAHeartOfGold a good guy deep down]], but is [[{{Badbutt}} kinda dangerous]] and [[CowboyCop plays by his own rules]]. Like, ''totally''.
* ShotgunWedding: Sal was rushed into marriage at a very young age by an angry father who caught him and his then-girlfriend fooling around, even though nothing sexual had actually happened between them (though it wasn't for lack of trying).
* StargateCity: Filmed in Vancouver.
* StealthSequel: [[Film/TwentyOneJumpStreet The movie.]]
** [[spoiler:SuddenSequelDeathSyndrome]]: [[spoiler:Hanson and Penhall are shot up by One-Percenter bikers]].
* SixthRanger: Richard Grieco's character, Dennis Booker, for one season. His character was then given his own short-lived spinoff.
* SuspiciouslySimilarSubstitute: David Barry Gray's Dean Garrett replacing Johnny Depp's Tom Hanson.
* TeacherStudentRomance: Happens with [[GirlOfTheWeek almost disturbing frequency.]] It helps that Johnny Depp's character was in his [[OlderThanTheyLook mid-twenties]], not actually a student, and in the most [[{{Egregious}} egregious]] example, met before he was actually assigned to her school.
** For bonus points, this happens in an episode that frequently mentions VanHalen.
* TrueCompanions
* VanityPlate
* VerySpecialEpisode: The show often dealt with hot-button issues, and often had a brief spot afterward with a phone number for the organization dedicated to addressing a particular social problem.
* WholeEpisodeFlashback: "Christmas in Saigon" is one of these in addition to being ADayInTheLimelight for Ioki. "Chapel of Love" is one for the rest of the cast, as they all reminisce about bad dates (though in Hoffs' case, the bad date happened during the timeframe of the episode).
* WholesomeCrossdresser: [[JohnnyDepp Johnny Depp's]] attraction to eyeliner didn't start with [[PiratesOfTheCaribbean Captain Jack Sparrow]] - during his time on this show, he was undercover in drag in "[[http://www.youtube.com/watch?v=B4bJr_gY2E0#t=4m34 In the Custody of a Clown]]" and looked far too convincing.
** In on episode, Hanson complains about being in drag for other cases, and laughs that it was getting him asked out by guys. Consider how [[AttractiveBentGender effective]] he is in drag, it's hard to tell if he's joking or just laughing it off.
** Harry dresses up as a woman so that his stakeout with Doug in season three looks like a regular date.
* WoobieOfTheWeek