As long as there has been cinema, filmmakers have been scouring through and adapting literature into films. Some are good, some are bad; some follow the arc of the novel exactly, and others are nothing at all like the book on which they are based, even if they cling to the basic skeleton of their source material.

But just because a film is nothing like the book, that doesn’t make it bad; it can often be of benefit to a film to shed some details from the book to convey a more succinct vision. Sometimes this lack of cohesion to the original work is intentional, as the filmmaker has different goals than the author. Occasionally, it is a failure of the filmmaker’s to either invest the effort, or possess the savvy to effectively adapt a novel to the screen. Regardless, intentional or not, there are many instances in which the film was nothing like the book on which it was based. Here are some of the most compelling instances.

Jeff Goldblum in The Fly

‘The Fly’ (1986) - I’ve Been Purified!

The Flyis a remake of a 1950s film that was based on a novella. In the 1986 Film,Jeff Goldblumdelivers a rousing performance as the repulsive shape-shifting lead, Seth Brundle. Brundle is on the verge of a massive scientific discovery involving teleportation, when a technological error results in the merging of his DNA with that of a housefly.

While this basic concept is the same as the source material, the similarities are mostly cosmetic, as the characters, the plot devices, the story-telling mechanisms (and basically everything else) are not at all the same. The original ‘the Fly’ film follows the arc of the book much more closely than the Cronenberg follow-up, but is a decidedly less compelling film (thoughstarringVincent Price, still worth a watch).

Shrek

‘Shrek’ (2001) - Noble Steed

The children’s picture book on which the 2001 Dreamworks classic is based, is about an ogre namedShrekwho saves an “ugly” princess, the similarities stop there. In the film, the audience is given much more detail surrounding the backstory of Shrek’s motivation, prodded by the nefarious Lord Farquaad (John Lithgow) into action.

Related:Howl’s Moving Castle: The Biggest Differences Between The Movie and The Book

Bruce Willis, Die Hard

The Shrek character, voiced expertly byMike Myersin the film, is given an entire universe of depth that the character from the book lacks. Additionally, we don’t really have a true concept for Donkey in the book either.

‘Die hard’ (1988) - Two Films, Four Books

The Die Hard backstory can be a bit confusing. TheBruce Willisfilm is based on a Book, which is the sequel to another book, which is based on a film which is based on two books (a bit confusing). The book to which the film is most closely bound is called:Nothing Lasts Forever. Unlike the film, in the book, the protagonist’s adult daughter is in the building instead of his ex-wife.

Related:Best Films That Take Place Over One Night

The book is much darker, and has much less debate surrounding its classification as Christmas material—it’s not. The characters, specifically the protagonist, are built very differently and make different decisions, in no small part because the John Mclean character from the novel is significantly older than that of the film character, and subsequently possesses a much different perspective than that of the Willis portrayed version.

‘The Cat in the Hat’ (2003) - Under Contract

This film adaptation of the classicDr. Seusscharacter represented more of a contractual obligation for its heavily make-upped lead actor, Mike Myers, than it did a true creative outlet (believe it or not). So frankly, the final product has absolutely zero of the whimsy that made the suess-source material so beloved in the first place, and instead is just plain weird.

Visually, the film delivered a fairly well composed seussian vision; much less subtle in its cartoonish nature compared to theRon HowardSuess film:The Grinch.The Cat in the Hattried to do too much and suffered for it.

Mike Myers as The Cat in the Hat holding a garden tool in The Cat in the Hat (2003)

‘Planet of the Apes’ (1968) - Whose Planet?

The Novel on whichPlanet of the Apesis based, was written by french author and swashbuckler: Pierre Boulle. The French novel differs dramaticallyfrom the original film and the subsequent remakesin many ways, but none so dramatic as the fact that the planet itself is different between the book and the film— one of the most important plot points in the film.

Furthermore, the whole book is told through a framing device which calls (intentionally) the story’s whole authenticity into question. Really, the only similarities are in the two words: “Planet”, and “Apes”, because the themes of the film and the book are on entirely separate trajectories (although both feature massive, but very different twists at the end).

Planet-of-the-Apes, Charlston Heston

‘Forrest Gump’ (1994) - Orangutan Buddy

It is hard to say that the beloved film adaptation of this book isnothinglike the source material, because there are so many similarities in the major plot points. However, the difference comes in the minor details, and in the way things ultimately play out for the titular character. Most people who have both read the book and seen the movie would likely agree that theTom Hanksinterpretation is more likable—nay,lovable, than the book version.

Related:’Forrest Gump’s Tom Hanks, Robert Zemeckis, and Eric Roth Reuniting With ‘Here’

The film, of course, ends on an extremely emotional note with Forrest and his son in a scene which masterfully mirrors one of the first in the film. The book ends much differently, specifically with Forrest hanging out with an orangutan and begging for change, playing as a one-man-band, while sleeping on the famous green bench with a homeless Lieutenant Dan (Gary Sinise). This ending tugs at the heart-strings decidedly less than the film ending.

‘Jaws’ (1975) - Trim the Fat

Jawsis a prime example of a novel that was used almost entirely as a jumping off point for a film, and not for its narrative content because the filmmakers had little intent from the start to recreate the book. DirectorSteven Speilbergallegedly found the characters from the novel unlikeable, and the studio was basically only interested in the main character (the shark) and the title.

Related:Scariest Movies You Didn’t Realize Are Based On Books

What the film gives you is an entirely stripped down version of the book’s storyline, with a few major retouches to the major characters who still remained. The film version is a classic, while being virtually unrecognizable from the source material because of the book’s focus on many subplots which were cut from the film. Unrecognizable, besides of course thedeadgive-away that is the shark, and the title.

Next:Book-to-Screen Adaptations Coming in 2022 Include ‘Salem’s Lot’ & ‘Deep Water’