In the French and German releases of the game, the character of Nimdok and his chapter as a whole were removed, because the chapter was based around a Nazi concentration camp. For nearly 30 years, it was rumored that the removal of Nimdok's chapter made the best ending unattainable. However, this was eventually disproven in 2023, when YouTube user StarlightPumpkins uploaded a video laying the rumor to rest by successfully achieving the best ending in the French release.

There are a few deleted scenes that never made it into the final game. Two of them are Gorrister feeding a live heart to a dog and Benny eating an infant child to survive.

The game was based on the 1967 science-fiction short story of the same name. Harlan Ellison, the short story's author, also worked on this game. Despite not being a fan of computer games and not owning a personal computer at the time, he co-authored the expanded storyline and wrote much of the game's dialogue, all on a mechanical typewriter, provided artwork of himself used for a mousepad within the game, and voiced "AM" the supercomputer.

In the final part of the game when playing with Ellen, she says "I'm an engineer, not a brain surgeon." This is thought to be a reference to Dr. McCoy from Star Trek who would often say "I'm a doctor, not a ____" . Harlan Elisson, one of the game's designers, also sold scripts to many television shows. One of them was Star Trek.