Before Ridley Scott’s name was ever mentioned, or the title Alien was in anyone’s thoughts, Dan O’Bannon met with struggling writer/producer Ron Shusett to discuss a potential collaboration. O’Bannon had been working on a sci-fi/horror script, but he was stuck with only a first act, so he’d hoped that Shusett’s input would help flesh things out and lead to a completed, sellable screenplay.
The unfinished script’s title was Memory, and, per Shusett’s recollections in Alien Vault, it was a real humdinger. In just that first act, a small, hideous alien latches onto the face of spaceship crew member and, shortly after that, a pint-sized creature busts its way out of said crew member’s chest and hauls ass out of the scene. O’Bannon's unforgettable visual was inspired by his own struggles with Crohn’s disease, a chronic, painful gastrointestinal disorder that he equated to an enemy within, but he had stopped writing after the first act.
Over 30 years later, those first-draft scenes, wisely kept intact by Scott and everyone else who worked on the project, hold up as Alien’s most terrifying images.