Studios and investors put a lot of money into movies, some more than others, with an expectation of a finished product they can sell. It doesn't always work that way. Movies that don't turn out so well are box-office flops, or else go straight to home video. There are a few rare films that got a lot of hype, especially surrounding the expensive stars who were expected to produce a hit, but were never released. Sometimes it's because they were completely awful films. But there are exceptions, such as Nothing Lasts Forever, which was supposed to be released in 1984.
In the same year that Bill Murray scored a global hit with Ghostbusters, he also appeared in the 1984 movie Nothing Lasts Forever, a sci-fi comedy from Saturday Night Live writer Tom Schiller. Largely shot in black and white, it's about a struggling artist living in New York (which has become a fascist state) and takes a bus trip to the Moon. Zack Galligan, who'd scored a hit of his own that same year with Gremlins, starred as the young lead, Murray played a lunar bus conductor, while the supporting cast also included Dan Aykroyd, Sam Jaffe, and Eddie Fisher.
It sounds like a quirky film, alright, but it isn't its lack of marketability that has left it sitting on a shelf for over 30 years and counting. According to Slate, legal problems involving the movie's use of copyrighted music and clips from classic movies have left it stuck in limbo. Aside from a couple of airings on TV, Nothing Lasts Forever has never had a theatrical or home release; someone leaked it to YouTube about five years ago, but this was blocked by Warner Bros.
Read about four other projects in which millions were spent on a top-notch cast, but the movie never saw the light of day at Den of Geek.