[[quoteright:350:http://static.tvtropes.org/pmwiki/pub/images/rsz_kartinka1_2153.jpg]]
[[caption-width-right:350:Probably the most known AnimatedAdaptation.]]

''Karlsson on the Roof'' is a trilogy of children's books written by Swedish author Creator/AstridLindgren. (''Karlsson-on-the-roof'', ''Karlsson Flies Again'' and ''Karlsson-on-the-Roof is Sneaking Around Again''), in which the main character is "Lillebror" (literally ''Little Brother'', named "Eric" in the English translation), the youngest of three children in an ordinary family who live in an apartment in Stockolm. His family is repeatedly described as completely ordinary, with a mum and a dad and three siblings. Big sister Bettan ("Betty" in the English translation) is boy-crazy, big brother Bosse ("Bobby" in the English translation) plays guitar and does poorly in school, and Lillebror, who is several years younger than his siblings spends a lot of time alone... at least until the day he makes an extremely extraordinary friend, namely the titular Karlsson-on-the-Roof.

Karlsson is a small, fat and [[SmallNameBigEgo highly overconfident]] [[VagueAge "man in his prime"]] who lives a small cottage on the rooftop of the apartment building. He comes and goes as he pleases, [[HeliCritter thanks to a propeller on his back, operated by a button on his stomach, that gives him the ability to fly]], and is often more than happy to show up when Lillebror feels lonely and needs a friend -- though he's by no means always an easy friend to have, with his often selfish and self-centered attitude and tendency to cause trouble and then fly off to let others take the blame. Still, he does have a lot of charm and inserts a lot of fun and excitement into Lillebror's somewhat monotone life, even if Lillebror's family for the most of the first book [[NotSoImaginaryFriend think that Karlsson is just an imaginary friend that Lillebror invented as a convenient scapegoat.]]

Lillebror and Karlsson have to deal with more than disbelieving parents, though; over the course of the books they have to tangle with a strict and hysterical housekeeper named Miss Bock, Lillebror's old cranky uncle Julius, two burglars named Fille and Rulle ("Cosh" and "Ruffy" in English), who go on to become recurring antagonists, and even the risk of discovery and exposure to the general public when newspapers begin printing pictures of a flying Karlsson and speculate whether he's a UFO or some secret foreign spy satellite.

The Karlsson stories have been adapted for both the big and the small screen a number of times. The earliest adaptations are the two Russian featurettes from 1968 and 1970, which were based on the first two books in the series and are part of the reason why [[GermansLoveDavidHasselhoff Karlsson is such a popular character in Russia that he's almost a Russian cultural icon]]. These were followed in 1974 by a Swedish live-action version called ''Världens Bästa Karlsson'' ("The Greatest Karlsson in the World"), which adapted the first book. Then, in 2002, another animated movie was released, this time a full-length theatrical feature based on the first and third book (primarily the third), produced in Norway and overseen by Ilon Wikland, the woman who had illustrated the original books.
This movie also spawned an animated TV series.
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!! The ''Karlsson on the Roof'' series provides examples of:

* [[ABoyAndHisX A Boy And His Not So Imaginary Friend]] ''and'' [[ABoyAndHisX A Boy And His Dog]]: Lillebror wants a dog more than anything in the world but his parents aren't too keen on him getting one. At the end of the first book, however, they relent, partly because they think that with a dog Lillebror won't be so lonely anymore and won't keep thinking up stories about Karlsson. It's only ''after'' Lillebror has gotten his new puppy that they actually meet Karlsson. The dog, Bimbo, remains Lillebror's trusty pet in the two following books, even if he never becomes the replacement for Karlsson that Lillebror's parents hoped he would -- though he and Karlsson get along perfectly well for the most part.
* AnnoyingYoungerSibling: Bosse and Bettan, who are both teenagers, tend to view seven year old Lillebror as this.
* AscendedExtra: Bettan's boyfriend Pelle appears only in one chapter in the original books, but has a larger role in the 1974 live-action adaptation.
* BigEater: Karlsson, who engages in a bit of HypocriticalHumor over the fact sometimes -- accusing ''others'' of being gluttons.
* BlueAndOrangeMorality: It would be wrong to say that Karlsson lacks morals, it's just that his sense of morality is mostly centered around what benefits him, or whoever he's feeling sorry for, at the moment.
* CanineCompanion: Bimbo to Lillebror in the second and third book, though he's often left behind (for obvious reasons) when Lillebror goes climbing on/flying over the rooftops with Karlsson.
* CanonForeigner: In the second Russian cartoon, Miss Bock has a cat, which does not appear in the original book and seems to be there mainly as a counterpart to Bimbo. Like Miss Bock, the cat starts out unfriendly but eventually warms to the protagonists.
* CharacterDevelopment: Weirdly enough, though Karlsson himself could have used a heavy dose of this, he more or less completely avoids it... though through his actions he inspires CharacterDevelopment in ''other'' people. Most notably affected are the grouchy uncle Julius and the overly-strict Miss Bock, who largely thanks to him become better and happier people.
* {{Cloudcuckoolander}}: Karlsson occasionally comes across as this with his nearly antagonistic relationship with anything resembling common sense.
* DeadpanSnarker: Karlsson, especially when interacting with Miss Bock or Uncle Julius.
** Bosse has this as his defining character trait; he is a very minor character in the books, but whenever he does appear, trust him to at some point make a snide or sarcastic remark. The 2002 animated movie takes this trait and runs with it, turning him into a wiseguy who constantly laughs at his own jokes.
*** Even Lillebror has his moments of this, usually when talking to his siblings.
* DecemberDecemberRomance: In the third book, between Miss Bock and Uncle Julius.
* DefrostingIceQueen: Miss Bock.
* {{Expy}}: Karlsson is a rare mixture of this and CharacterizationMarchesOn for Mr. Lijonkvast, a character from the earlier Lindgren short story ''I Skymningslandet'' ("In The Land of Twilight"). Mr. Lijonkvast was also a small man who could fly and took a small boy out on adventures -- though only in the hour of twilight, when the world was different. Lindgren has described how she several years later returned to this character, only to find that over the years he'd lost his "perfect friend and companion" tones and changed into a sulky, selfish SmallNameBigEgo -- the character who became Karlsson-on-the-Roof.
** It might be a coincidence, but Fille and Rulle are ''suspiciously'' similar to Blom and Dunder-Karlsson from ''Literature/PippiLongstocking''.
* GrumpyOldMan: Lillebror's uncle Julius is a particularly tiresome example, at least at first.
* HeliCritter: Karlsson, of course. It's never explained just how his propeller works, or how he got it. He claims to have invented it himself, but you never know with him.
* HypocriticalHumor: Karlsson seems to be completely ignorant of his own flaws, but has no problems spotting them in others.
* JerkAss: Uncle Julius, pre-CharacterDevelopment.
* JerkWithAHeartOfGold: Karlsson. He's selfish, sulky, greedy and with an ego the size of a planet, but he's not ultimately a bad or malicious person.
** Miss Bock is haughty, strict, temperamental, and slightly unfair -- upon her introduction she seems like she's going to be a BabysitterFromHell, but it turns out she has many redeeming qualities.
* KarmaHoudini: Karlsson gets up to a ''lot'' of mischief, but never suffers any consequences. This is probably why a lot of readers tend to find him less likeable as they grow older -- for younger readers, he's an EscapistCharacter who gets to do all the things they all ''wish'' they could get away with.
* LethalChef: Miss Bock has traces of both this and CordonBleughChef, though her cooking does seem to be an acquired taste.
* TheMunchausen: Of all of Astrid Lindgren's characters, Karlsson is second only to Literature/PippiLongstocking when it comes to telling of tall tales -- though where Pippi will cheerfully admit that she's lying if called out on it, Karlsson will generally get angry or sulk if you don't believe him.
* NonAnswer: Karlsson's answer about his age that he's a man in his prime isn't very helpful.
* NotSoImaginaryFriend: Karlsson in the first book. Subverted in the second and third.
** The first Russian cartoon leaves it ambiguous whether he's real or not, as only Lillebror ever sees him, and he vanishes without a trace at the end -- though the second cartoon confirms that he ''is'' real, since Miss Bock and her cat also meet him.
* OnlyKnownByTheirNickname: Lillebror's real name is Svante, but since he's the youngest brother he's usually just called "Lillebror" (little brother) by his family and even his friends. Averted in the English translation of the book, where everyone calls him "Eric.''
* PutOnABus: Lillebror's two classmates, Krister and Gunilla (Christopher and Bridget in the English translation), play semi-major parts in the first book, but don't appear in the two last ones, though they are mentioned a couple of times to assure us they're still around, just not on-screen.
* ScrewThisImOuttaHere: Karlsson has a tendency to threaten with this if things don't go his way -- he usually stays, though, because Lillebror is always quick to soothe his hurt feelings.
* SitcomArchNemesis: Upon her introduction in the second book, Miss Bock quickly becomes this to Karlsson.
* {{Spoonerism}}: Fille is prone to these when he's frightened.
* SmallNameBigEgo: Karlsson has an unshakable faith in himself and claims to be the world champion of everything -- though it's shown time and time again that he ''really'' isn't. His ability to fly does help him pull off a number of things, though.
* ThoseTwoBadGuys: The two burglars, Fille and Rulle.
* TheFairFolk: There is a theory that Karlsson might be a modernized urban faerie. Indeed, some of Lindgren's other works involve the encounters between children and beings that are best described as faeries, elves and such, so this topic is most certainly not foreign to her. That would explain Karlsson's mischievous streak and VagueAge, among other things. It should be noted that while Karlsson is undoubtedly a JerkAss by human standards, he's actually rather nice for a faerie.
* TheUnseen: Miss Bock's sister Frida is constantly referred to and discussed, but never actually appears.
* VagueAge: Is Karlsson a child or a very small, [[{{Manchild}} very childish adult]]? The answer is deliberately kept unclear -- Karlsson when asked his age just answers that he's "a man in his prime." The 1974 live-action adaptation adds fuel to this by having a young boy play Karlsson, though dubbed over with a grown man's voice, and wearing a hairstyle that carefully hints of premature baldness.
** His indeterminable age might be related to TheFairFolk theory.
** In a Russian theatrical play (1971), Karlsson is played by an adult actor, while Lillebror's age is about the same as in the book. Some people find it a bit creepy.
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