Why did The Princess Bride never get a sequel? Directed by Rob Reiner, and based upon William Goldman's 1973 novel of the same name, The Princess Bride was a critical hit yet only a modest box-office success upon release in 1987. Nonetheless, its enduring popularity as a novel and a film have long inspired talk of a sequel, if only because Goldman considered writing one.
The original novel of The Princess Bride was presented as being the "good parts" of a longer story by S. Morgenstern, and included action, fantasy, romance, and fairy tale elements, as farm boy turned pirate Westley attempts to rescue his true love, Buttercup. The sequel would have revisited these characters, with revised editions of The Princess Bride novel including the first chapter of a new story called Buttercup's Baby. It tells the story of the heroes' escape to One Tree Island, and the kidnapping of Westley and Buttercup's baby by a skinless-faced madman.
Despite Goldman saying in later years that he tried to crack the story, The Princess Bride sequel never materialized in either print or film, although the 30th-anniversary edition of the book did promise it would be finished for the 50th anniversary in 2023. Sadly, Goldman passed away in 2018, so now that can't happen. Without a finished novel (much less an adapted screenplay) there is almost no chance of a Princess Bride movie sequel being made. Buttercup herself, actress Robin Wright, told E! that the general consensus of the film's original cast is "Don’t ruin it. Please don’t ruin it."
There is debate as to whether Buttercup's Baby was really ever going to happen. Goldman originally claimed he was trying to secure permission to adapt Buttercup's Baby into a "good parts" edition, but that the estate of S. Morgenstern had already signed Stephen King to do it and there was a legal battle that ended with him only being allowed to adapt the first chapter. This was also a joke between colleagues, as King and Goldman had become friendly after Goldman wrote the screenplays for several adaptations of King's work. Some fans believe the sample chapter was included to convince fans to buy the new editions of The Princess Bride novel, or that it was just part of the joke. Regardless of the truth, the story was never finished.
Either way, there would likely be some issues with the rights for a Princess Bride sequel. When The Princess Bride was first optioned for a movie, Goldman bought back the film rights with his own money after the studio management changed. Over a decade passed before he allowed someone to adapt the novel into a film, and then only because director Rob Reiner was a huge fan of the book. Given that, it seems unlikely that Goldman's estate would grant permission for anyone else to finish the story as a book or film, although a lot of people want to remake The Princess Bride apparently.
Even if Goldman's estate were interested in crafting a sequel without Goldman, the idea of a new Princess Bride movie is controversial. Stephen King, the one writer who might be allowed to touch the project, said that "if there's ever going to be (a sequel), Bill will have to write it" before Goldman's death. Given all of that, it seems that a sequel to The Princess Bride is inconceivable.