Movie sequels have a reputation for being cheap knock-offs of the original, and a number of canceled projects would've further proven that point if they'd actually happened. When a movie makes a profit, studios often want to capitalize and expand the story in future titles. For instance, Barbie was a smash hit, so Mattel and Warner Bros. instantly put out the idea of a Barbie 2, as well as several other toy-based movie ideas. This was to the dismay of audiences, who appreciated Barbie for not being linked to a larger franchise.
Not all sequels are bad, of course. Plenty of movie franchises got better after their first installment, with sequels positively expanding on the ideas and worlds created in an original film. With that being said, there's no telling how any planned film release would've actually performed. The only measures that can be judged are the concept for the film, how well the previous installment wrapped up its storylines, and whether the original was of a high enough quality to merit a sequel.
10 Nick Cave's Gladiator 2
Gladiator 2 is happening, just not in the form envisioned by musician Nick Cave. Following the massive success of Gladiator, ideas for sequels circulated around Hollywood for years, with Cave's script standing out. Cave is a fantastic musician, known by younger audiences for his songs used in Peaky Blinders and Harry Potter and the Deathly Hallows: Part 1. However, he isn't known for his screenwriting, making his Gladiator 2 script about Roman mythology far more surprising. The script would've seen Maximus in Elysium on a path back to life, a fantastical story arc that would feel too farfetched compared to the original film.
9 The Departed 2
The Departed is based on the Hong Kong film Infernal Affairs, which received two sequels, but turning the movie into a similar franchise probably wouldn't have worked for the American remake. Similar to Infernal Affairs 2, Mark Wahlberg's plan for The Departed 2 wouldn't have been a direct sequel, but rather a story taking place before, during, and after the first film. Wahlberg described attempting a pitch for the film that didn't go very well. The Departed would be a difficult film to continue properly, as almost every character dies, and the story serves its purpose as an intense, exhilarating crime thriller that works so well as a one-off.
8 The Dark Knight 4
The Dark Knight Trilogy is wrapped up neatly. While the third film isn't perfect, the ending is emotional and satisfying. Finding a way to bring Batman back would damage that ending, and Joseph Gordon-Levitt picking up the mantle wouldn't have been as believable as Christian Bale. Following The Dark Knight Rises, Warner Bros. approached Bale and director Christopher Nolan about returning for another film, which they both declined. Since then, Bale said he'd return as Batman if Nolan asked, but Nolan has outright declined any interest in returning.
7 Green Lantern 2
Green Lantern is almost unanimously agreed to be one of the most abysmal superhero films ever, despite it originally being planned to have sequels and to kickstart the DC Universe on film. Green Lantern's post-credit scene sees Mark Strong's Sinestro becoming the Yellow Lantern villain he's known as, an idea that was never fulfilled due to the cancelation of Green Lantern 2. The original was a massive box-office bomb, and a critical failure, leaving no room for any sequels. While Mark Strong as Sinestro is an appealing thought, there was no good reason to continue making Green Lantern films.
6 Independence Day 3
Independence Day was one of the highest-grossing and most popular films of the 1990s, making it surprising that it took 20 years for a sequel to release. Independence Day: Resurgence is an awful sequel, and was considered a failure at the box office. While an Independence Day 3 film was planned with a possible space mission to attack the aliens on their own turf, the idea has since been canceled.
5 The Golden Com 2
The His Dark Materials TV series has already redeemed the Golden Com film, which was one of the most disappointing fantasy book adaptations ever. While the adaptation had a great cast, including Daniel Craig, Nicole Kidman, Eva Green, and Ian McKellen, the film left out most of the commentary on organized religion that defined the depth of the novels. After the first film was a box office failure, plans to continue the franchise with sequels were canceled. Continuing without key elements of the story, or trying to shoehorn them in later, would've likely resulted in a messy sequel.
4 Gods Of Mars
John Carter was one of the biggest box office bombs in the history of film, and a major disappointment for Disney, which was trying to establish a new franchise. Taylor Kitsch was set to become Hollywood's latest franchise action star with John Carter and Battleship sequels, but both were immediately canceled as the films colossally failed only months apart from each other. For fans of the beloved Barsoom novels by Edgar Rice Burroughs, John Carter was a major departure from the story, and a Gods of Mars sequel likely wouldn't have been able to restore the narrative.
3 Ei8ht
Se7en is not a movie that needs a sequel, as it's a standalone thriller film that relies on its writing, director, and stars, all of which are elements that a sequel would have lacked. A plan for a sequel, ridiculously titled Ei8ht, was introduced to David Fincher, Brad Pitt, and Morgan Freeman, all of whom declined to take part. The story was meant to follow an FBI utilizing a psychic to track down a serial killer. The idea for the film finally got used for 2015's Solace, which received a 24% critic score on Rotten Tomatoes.
2 Gump & Co.
Following Forrest Gump, author Winston Groom wrote a novel titled Gump & Co. as a sequel. While Forrest Gump was a major success and Academy Award winner, neither its star, Tom Hanks, nor director Robert Zemeckis expressed any interest in returning for a sequel. While the event of 9/11 was a major factor in the film not going forward, Tom Hanks has also said that the conversations regarding a sequel didn't even last an hour before they decided not to do it (via Variety).
1 Mrs. Doubtfire 2
A sequel to Mrs. Doubtfire was planned, with Robin Williams actually expected to appear in the project before his tragic ing. Going forward with the project without the late great actor would've been a huge misstep. Director Chris Columbus has even criticized the many theater adaptations of Mrs. Doubtfire, stating that the story is nothing without Robin Williams' talent.
