Ultimately, Brandywine Productions agreed to produce the film for 20th Century Fox. While Scott was focused on staying under budget, there was another serious drama going on. According to O'Bannon, producers David Giler and Walter Hill plotted to steal his writing credit. Giler has publicly disparaged O'Bannon's screenplay, and he and Hill took it upon themselves to correct what they viewed as shortcomings, cooking up a total of eight rewrites. The screen credits would eventually head to arbitration.
According to Giler, the screenplay required such intensive rewrites that he and Hill ended up "[changing] all the dialogue. Every word of it." (A line-by-line comparison between a later Giler-Hill draft and O'Bannon's original suggests Giler is either mistaken or knowingly exaggerating.) Giler credits his work with Hill for "adding the feminist elements everyone is talking about. [Walter Hill and I] gave the characters texture, functions. In O'Bannon's draft, they were totally different, military types. All men."
We're left with four major Aliens, and we're not talking about the so-called Quadrilogy. There's O'Bannon's expansion of his Star Beast screenplay, featuring the xenomorph, the space jockey, and the wrecked ship, but also an elaborate pyramid-shaped egg silo megastructure, no androids, no women, and some space truckers with really outlandish names—Standard, Faust, Melkonis, Broussard, and Roby instead of Ripley. Roby?
Then there's Hill and Giler's rewrite with Ripley and Dallas and the rest of the gang, a vast corporate conspiracy involving human-looking androids, and a big cylindrical silo made out of cement—but also, in certain drafts, a time-travel-based plotline featuring Jack the Ripper, Hercules, and Genghis Khan, and, in their favorite draft, a human space jockey and no alien! Then there's the Alien that, against daunting odds, Scott and his team somehow made despite the squabbling and confusion.
Finally, there's Alien: The Director's Cut, Scott's definitive version, which actually bears little resemblance to O'Bannon's vision. "I didn't write 'play it slow,' which is what Ridley did!" complained the screenwriter. "He played it slow and he was damn lucky that slow worked so well." As Foss put it to Den of Geek, "Poor old Dan O'Bannon, the bloke whose concept it was, just got absolutely shafted… I kind of got the impression that Ridley [Scott] was quietly going his own way… really just ignoring months of input" from the pre-production team.