Indiana Jones and the Kingdom of the Crystal Skull screenwriter David Koepp recently admitted that the 2008 sequel's "aliens" might have been a mistake.

Koepp opened up about the controversial decision to include interdimensional beings resembling extra-terrestrials in the fourth Indiana Jones movie, in an episode of the Script Apart podcast. "I was never happy with the idea [of including alien-like creatures in Indiana Jones and the Kingdom of the Crystal Skull]," he said. "When I came on, I tried to convince [director Steven Spielberg and franchise co-creator George Lucas] to change it -- I had this other idea. They didn't want to change it."

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"I'm not saying mine would've been better," Koepp continued. "But I think that a lot of the pushback that movie got, in a larger sense aside from little things people might not have liked -- that were too silly or whatever -- the larger one was that [fans said] 'We don't feel like aliens should've been in an Indiana Jones movie.' Fair enough, in retrospect, you're probably right [laughs]." The scribe declined to reveal what his alternative idea for the fourth Indy movie's McGuffin was, joking that he'd prefer it to remain "this misty, ethereal thing that's probably brilliant" in fans' collective imaginations.

Harrison Ford Announces Indiana Jones' Return

A fifth Indiana Jones film is currently in production, with Jez Butterworth, John-Henry Butterworth and James Mangold taking over scriptwriting duties from Koepp. Star Harrison Ford unveiled the first look at the upcoming sequel during the Star Wars Celebration event in May 2022, which depicted the aged adventurer in silhouette as he navigates a dark cavern. Ford also announced the film's June 2023 release date as part of the presentation.

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Neither Disney nor Lucasfilm have yet confirmed the official title for Indiana Jones 5, although a photo of a branded baseball cap belonging to producer Frank Marshall has fueled speculation the film is called "Indy." If true, this would mark a significant break from the wordier, Saturday matinee-inspired naming convention established by the previous entries in the franchise.

Regardless of whether Indiana Jones 5 bucks tradition with its name or not, the upcoming sequel will still break new ground for the series by being Indy's first outing not helmed by Spielberg, as Mangold will direct, instead. Legendary composer John Williams has also suggested that Ford might retire after Indiana Jones 5, potentially leaving the future of the franchise itself in doubt.

Indiana Jones 5 arrives in theaters on June 30, 2023.

Source: Script Apart