Admittedly, even when a book or book series are well-known, it's often the case that a movie adaptation will become more famous. You can blame human laziness or shallowness, but generally, watching a two-hour movie is seen as a more desirable option than reading a book that will take many more hours to finish. That's not to say this is fair or justified, nor is it the case that this always happens... but it's not too earth-shattering when it does.

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Still, even in many of these cases, the book that serves as a starting point for a movie adaptation remains well-known. Take movies based on young adult book series: even someone who hasn't read The Hunger Games novels, for example, will likely know they came first. The following films, on the other hand, have largely overshadowed the books they were based on. As a result, some may be surprised to learn that these movies were based on pre-existing stories in the first place.

'Shrek' (2001)

shrek

The original Shrek was quite a revolutionary film. It became immensely popular upon release, and appreciation for it - both sincere and ironic - has only skyrocketed since 2001. It was a fairytale parody, with plenty of irreverent humor, but at the same time, also served as a genuinely enjoyable and even heartfelt fantasy story in its own way.

The foundations for Shrek, however, came from a children's book published 11 years before the movie's year of release. Given it was only about 30 pages long, it only really contains the basics of what the film depicted: Shrek's an ogre, he has a donkey sidekick, and there's a mission to rescue a princess. But otherwise, the storyline of each is pretty different. Still, the children's book was where the character originated, making the original Shrek (not its sequels, though) a surprising adaptation.

'Crouching Tiger, Hidden Dragon' (2000)

Michelle Yeoh in Crouching Tiger Hidden Dragon
Image via Sony 

One of the most iconic martial arts movies of all time, Crouching Tiger, Hidden Dragon blends action, mystery, romance, and tragedy into a narrative that's both epic and intimate. The plot, which concerns a stolen sword and the various people who want it, allows for plenty of great action sequences and beautiful visuals.

The story upon which Crouching Tiger, Hidden Dragon is based goes back almost 60 years before its release, and was actually the fourth entry in a five-part collection of stories known as the Crane-Iron Series. Interestingly, it got an adaptation in the 1950s, though that's believed to be a permanently lost film. As it stands, the 2000 movie has become far more well-known than the original story, especially outside of China, given Crouching Tiger, Hidden Dragon's immense international success.

'Psycho' (1960)

Anthony Perkin as Norman Bates in Psycho (1960)

There's an interesting story behind the novel that Psycho was based on. It came out in 1959, and impressed Alfred Hitchcock so much that he went to great lengths in order for no one to learn he was making an adaptation. After all, Psycho has one of the most shocking plot twists of all time, and it's not one that Hitchcock wanted people to know in advance.

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It's hard to confirm for sure, but allegedly, Hitchcock tried to buy as many copies of the book as possible from as many bookstores as he could to keep Psycho's surprises surprising. It may be one factor that's led to the book being mostly forgotten, though, of course, the movie has gone on to become one of the most famous horror/thrillers of all time.

'There Will Be Blood' (2007)

A man sitting on a chair smoking a pipe

Whilst many of Paul Thomas Anderson's films are written as original screenplays, his 2007 film, There Will Be Blood, is a loose adaptation of a 1927 novel called Oil! While character names and certain plot elements differ between the two, each deals with a wealthy, tyrannical millionaire who makes his fortune from mining oil, as well as his strained relationships and moral decline.

There Will Be Blood might be Anderson's best-known film (or it's at least right up there), and was a major award contender, becoming one of its decade's most praised films. The adaptation here is quite loose, with the movie having a similar set-up but branching off dramatically at a certain point, but either way, it's more well-known than the 1927 novel.

'Battle Royale' (2000)

Battle royale the entire cast take a class photo before the events of the movie unfold

Within a very short space of time, Battle Royale - the iconic Japanese story about a high-school class forced into a gruesome fight to the death among each other - was a novel in 1999, a movie in 2000 (which got a 2003 sequel), and a manga series that was published between 2000-2005.

The manga is fairly well-known (even inspiring Squid Game, apparently), though it's debatable whether it's more well-known than the 2000 film. Still, each is more established than the original 1999 novel, to the point where it may come as a shock to those familiar with the manga or movie to find out that neither was the first time the story was told.

'The Iron Giant' (1999)

a giant robot looks down at a young boy

The setting for The Iron Giant makes sense once you find out it's loosely based on a novel, The Iron Man, from the 1950s. While the small-town setting and nostalgic 1950s aesthetic make the film feel unique in more modern times, to read the story close to its release wouldn't have been at all surprising.

Still, given the film is heralded as a cult classic - or an example of a critically acclaimed film that failed to pull in big numbers at the box office - it's come to overshadow the novel. It might not be the most dramatic example of a movie becoming better known than the book it's based on, as the similarities are minor, and the film itself still is a little underrated, but overall, it qualifies.

'Once Upon a Time in America' (1984)

Once Upon a Time in America

Sergio Leone was a hugely underrated and underappreciated filmmaker during his time on Earth, and only really began to get the appreciation he deserved after he passed away. No film of his got snubbed as badly as his 1984 masterpiece (and directorial swansong) Once Upon a Time in America, a decades-spanning gangster movie that got cut down and even butchered for its U.S. release.

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While the film has at least gone on to become a properly appreciated classic, the same can't be said for the 1952 novel it was loosely based on, The Hoods. Interestingly, the author, Harry Grey, based the main character on himself, and his true-life experiences, meaning the novel (and by extension, the movie) are semi-autobiographical. Regardless, it hasn't really allowed The Hoods to emerge from the shadow cast over it by Once Upon a Time in America.

'Who Framed Roger Rabbit' (1988)

Who Framed Roger Rabbit
Mickey Mouse, Bugs Bunny, Bob Hoskins (1988)

Seven years before the beloved classic Who Framed Roger Rabbit was released came the novel, the similarly titled Who Censored Roger Rabbit? It wasn't just the titles that were different: the storylines were, too. For example, in the book, Roger Rabbit doesn't serve as protagonist Eddie's sidekick: Roger dies early on, and it's his death that Eddie investigates.

It's probably for the best that the story was retooled to allow Roger a supporting role. Indeed, the book's author, Gary K. Wolf, may have agreed, as the sequels to Who Censored Roger Rabbit? that he wrote in the 1990s follow the movie's plot more than the original novel's.

'Children of Men' (2006)

Theo (Clive Owen) and Kee (Clare-Hope Ashitey) walking past soldiers with a baby in 'Children of Men' (2006)

Children of Men is such a visually spectacular movie that it's almost hard to imagine it as anything but a film. Its bleak depiction of a future where the human race can no longer reproduce is such a rollercoaster ride as a movie, with awe-inspiring camerawork and visceral visuals in its tense, relentless action sequences that will increase the pulse of any viewer.

However, in 1992, the novel, The Children of Men, was published and serves as the basis upon which the 2006 film is based. The book was still relatively well-received, but the film was so powerful (and still retains its impact) that it's become the more well-known of the two.

'Mrs. Doubtfire' (1993)

Robin Williams as Mrs. Doubtfire and Sally Fields as Miranda Hillard in Mrs. Doubtfire
Image via 20th Century Fox

In one of Robin Williams' best-known roles, he plays a recently divorced father who disguises himself as an elderly cleaning lady in order to stay in his house and spend time with his kids. It's far-fetched but entertaining, and Williams committed himself to the role so strongly that it ended up becoming a minor classic.

It may be surprising for some to learn, then, that Mrs. Doubtfire was based on a British book called Madame Doubtfire. It has some differences from the better-known movie - and may be a little darker overall - but the premises are the same, making Mrs. Doubtfire a relatively faithful (and more famous) adaptation of the novel.

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