As most fans of the franchise probably know, the climax of Indiana Jones and the Kingdom of the Crystal Skull confirms that the film’s titular skulls are not biblical or magical in nature, as has been the case in previous films in the franchise. Instead, they are the skulls of interdimensional aliens who leave Earth once the skulls are returned to their skeletons.
During a recent interview on the Script Apart podcast (via Comic Book), David Koepp spoke about his involvement in the development of Indiana Jones and the Kingdom of the Crystal Skull. Koepp credited the shift to extraterrestrial life as the film’s central McGuffin, admitting that he was “never happy with the idea [of ‘aliens’]’ as the main plot of the film.
In fact, Koepp admitted he struggled to take the story in a different direction. Koepp noted his concerns about the inclusion of extraterrestrials in the film, saying, “When I came in, I was trying to persuade [Steven Spielberg and George Lucas] to change it – I had this other idea. They didn’t want to change it. I’m not saying mine would have been any better. But I think a big part of the backlash this movie got, in the larger sense, aside from little things that people might not have liked — that were too silly or whatever — the bigger one was that [fans said]’We don’t think aliens should have been in an Indiana Jones film.’”