Josh Boone intended this film to be the first in a trilogy, with the second film to be an alien invasion movie featuring the alien mutant Warlock, and then the third and final installment to be a supernatural, apocalyptic horror movie based on the X-Men comic event "Inferno" (demons invade the Earth and Magik plays a major role). After Disney's purchase of Fox, all X-Men-related films in development were cancelled, including Boone's trilogy.
Josh Boone admitted that he found shooting to be stressful, as he felt "a bit neutered" because he had to tone down the film from his original "full horror" ideas.
The film had five release dates. It was originally slated to debut on April 13, 2018, but was first delayed to February 19, 2019, in order to conduct reshoots. Later, it was pushed back to August 2, 2019, while Disney finalized its purchase of Fox. The film was pushed back yet again to April 3, 2020, to make room for the release of X-Men: Dark Phoenix (2019). On March 12, 2020, it was postponed due to the COVID-19 pandemic. On May 13, 2020, its new release date of August 28, 2020 was announced, and the film was finally released in theaters on that date.