In the years before the Disney buyout, Fox had seemingly found a key to success for its struggling X-Men franchise: Make spinoffs completely unlike the typical X-Men films. While the mainline series has continued to struggle, two wackily comedic Deadpool movies and the gritty Western Logan, as well as the psychedelic Legion on TV, offered distinctive, adult, artistically satisfying experiences unlike any other superhero movies or TV series.
Based on the trailer released in October 2017, Josh Boone's The New Mutants looked to continue the trend of successfully melding superhero stories with other genres, in this case supernatural horror. Two major delays later, the "success" of the final film, or even whether it gets released at all, is in doubt.
The first major delay on The New Mutants was actually understandable. Fox purportedly wanted to take advantage of standard reshoots to ratchet up the horror elements, bringing it more in line with Boone's initial pitch and expectations from the trailer. The studio was initially skeptical about going too far with the scares, but then It happened.
The record-shattering box office of that September 2017 Stephen King adaptation inspired Fox to play up the horror in The New Mutants' trailer. With the trailer received well, the initial release date delay from April 13, 2018 to Feb. 22, 2019 seemed reasonable enough and a good chance to improve the movie.
Boone reportedly reached a cut of the film he was happy with by March of 2018, but the studio demanded further reshoots, resulting in a delay to The New Mutants that pushed the film to its current release date of Aug. 2. At this point, the studio pushback had gone in the complete opposite direction of how it had started.
While at first the studio pressured Boone to tone down the horror, now the studio was pushing him to make the movie even scarier. Results from test screenings were positive overall, but the general feedback was that the film wasn't quite scary enough.
The slated reshoots have now extended far beyond the initial plans. Up to half of the entire movie is rumored to be reshot. One notable change is that the post-credits tease, which was originally supposed to feature Jon Hamm as Mr. Sinister, has been replaced with a tease for a new villain played by Antonio Banderas. There are rumors that multiple new characters have been added to the film.