Steven Spielberg and George Lucas‘ creative clash over “Indiana Jones and the Kingdom of the Crystal Skull” was recently revealed in a Spielberg oral history published by Vulture. Franchise producer Kathleen Kennedy noted how Spielberg and leading man Harrison Ford were both “struggling with the movie” because “they didn’t want to do a ‘Raiders’ movie that involved aliens, and they kind of got into a fight with George about it.”

“I wanted it to be kind of a ‘War of the Worlds’ sort of thing,” Lucas remembered. “Harrison said, ‘I’m not going to do another science-fiction movie.’ And Steven said, ‘I’m not going to do another science-fiction movie.’ I said, ‘Steven, this is perfect because it’s the 1950s, when flying saucers were a whole thing,’ but he said ‘no.’ We did about five scripts, and finally Steve and I compromised: ‘Look, what if they’re not aliens but from another dimension.'”

According to Kennedy, Spielberg and Ford “were not 100 percent on board” with the story direction of “Crystal Skull,” which is “why the movie, out of the four that Steven made, is the weakest. And that’s why Harrison was so deeply committed to ‘Dial of Destiny Destiny.’ He didn’t want [‘Crystal Skull’] to be the end.”

“Indiana Jones and the Kingdom of the Crystal Skull” is the franchise’s fourth installment, picking up with Ford’s adventure-loving archeologist in 1957 as he faces off against against Soviet KGB in the search for a telepathic crystal skull. Reviews were largely mixed for the sequel, which opened in May 2008 and grossed a strong $786 million worldwide.

“Nineteen years after their last adventure, director Steven Spielberg and star Harrison Ford have no trouble getting back in the groove with a story and style very much in keeping with what has made the series so perennially popular,” read Variety’s positive review of the film.

Ford returned as Indiana Jones in 2023’s “Dial of Destiny,” the only “Indiana Jones” movie not to be directed by Steven Spielberg. James Mangold took over filmmaking duties on the sequel, which earned negative reviews and underperformed with $384 million at the box office.