Films often start out completely different to the finished version that we see in cinemas, often sequels become original movies, or original movies are rewritten to be sequels of existing properties.
Other times films start out in one genre only to be reshaped during filming, or in this case, some start life as mature films only to be changed to something more family-friendly...
1. Scooby Doo (2002)
Before he wrote and directed Guardians of the Galaxy, James Gunn wrote the screenplay for a darker and edgier Scooby Doo live-action film, with direct references to Shaggy's marijuana habit, as well as Velma and Daphne in flesh-revealing outfits engaging in a lesbian fling.
The R-rated story, which would poke fun at the original animated series, was moved towards the clean-cut cartoon tone of the cartoon by the studio, and Gunn was made to rewrite it into the live-action family film that was released.
Gunn later went on to explain: "I had written an edgier film geared toward older kids and adults, and the studio ended [up] pushing it into a clean cut children's film.
"The first cut was rated R by the MPAA, and the female stars' cleavage was CGI'd away so as not to offend. But, you know, such is life.
I had a lot of fun making this movie, regardless of all that. And I was also able to eat, buy a car, and a house because of it."
2. Shrek (2001)
It is widely known that before Mike Myers voiced the lovable ogre, it was Myers' Saturday Night Live co-star Chris Farley that was cast as the voice of Shrek, with the comedy star recording 80-90% of the dialogue before his death.
When Myers came on board, he insisted on a complete script rewrite to remove any trace of Farley's version as he didn't want to be influenced by Farley's interpretation.
The original script written for Farley would have been a much more adult version of the fairytale parody aimed at adults and teenagers.
A storyboard reel with some of Farley's dialogue was released in 2015, showing the different approach that Farley brought to the animation.
3. Honey, I Shrunk the Kids (1989)
The much-loved family adventure movie was written by Stuart Gordon, Brian Yuzna and Ed Naha, who were all well known for writing schlocky horror movies such as Troll, Re-Animator and Dolls.
Their original script featured five main kids, one of which would die during the sprinkler sequence.
This was obviously rewritten into a family-friendly, non-fatal film, albeit one with a quite intense scorpion scene.
4. Galaxy Quest (1999)
The affectionate parody of sci-fi films and TV series like Star Trek boasted a cast including Sigourney Weaver, Tim Allen and Alan Rickman and was well received and went on to become a cult classic among sci-fi fans, and bizarrely, Star Trek fans voted it the 7th best Star Trek film of all time.
The film originally received an R-rating, and director Dean Parisot and star Tim Allen explained that the original tone was much darker and raunchier with more violence, bloodshed and foul language.
A lot of this was cut and the film was re-edited to emphasise the comedy, with the swearing memorably being dubbed over ("f*ck that" became "screw that), and the recut version was given a PG rating.
7. E.T. the Extra-Terrestrial (1982)
Steven Spielberg's alien tale is one of the most-loved family films of all times, but it started off as a sequel to Close Encounters of the Third Kind titled Night Skies.
While shooting Raiders of the Lost Ark, Spielberg read the Night Skies script to screenwriter (and girlfriend of Harrison Ford) Melissa Mathison, who cried after hearing the story about a sweet alien who strikes up a relationship with a child.
When he finished Raiders, Spielberg and Mathison set about turning Night Skies into E.T. the Extra-Terrestrial, while also managing to also adapt aspects of the script into horror classic Poltergeist.
8. Kangaroo Jack (2003)
The buddy-action comedy film starring Jerry O'Connell, Michael Shannon and Christopher Walken was originally titled 'Down and Under' and was a mafia comedy in the style of Robert De Niro's 1988 action comedy Midnight Run.
The film about two childhood friends who are forced by the mob to deliver $50,000 to Australia, which goes awry when a wild kangaroo steals the bag with the money, didn't impress producers when they saw the test footage.
Inspired by Disney's Snow Dogs, producer Jerry Bruckheimer shot new scenes with a CGI kangaroo that talks and the marketing heavily leaned on the film's talking kangaroo.
The only instance of the talking kangaroo was a short dream sequence, and many families, which were fooled into seeing the film with a sassy, wise-cracking kangaroo, were left disappointed by the mediocre film.
9. Old Dogs (2009)
The largely-forgotten comedy stars Robin Williams and John Travolta as business partners whose lives are turned upside-down when they become temporary guardians of seven-year-old twins.
Disney's Touchstone Pictures planned for the film to be an R-rated release, but disastrous test screenings prompted Disney to recut and reshoot the film, cutting 19 minutes out of the film and removing all of the adult jokes.
The family-friendly film was then released by Walt Disney Pictures, and despite a healthy box office return, it was still a disappointment and earned four Razzie Award nominations for Worst Picture, Worst Actor, Worst Supporting Actress and Worst Director.
10. Mousehunt (1997)
The black comedy, based loosely on the board game, became another victim to a bad reaction from its test screening, leading to a rewrite for kids.
The comedy, starring British stand-up Lee Evans and Nathan Lane as two Laurel and Hardy-like brothers who inherit a house and try to eradicate a canny mouse who also calls it home, was the directorial debut of Gore Verbinski.
Originally the film was an even blacker comedy, written and shot for a teenage and adult audience before the negative reaction saw Dreamworks re-cut the film for families.
Feeling a lot like a Tom & Jerry cartoon with live actors, despite the film's family rating it still maintained a lot of the dark humour from the original script.