A rare 1963 U.S half sheet original vintage movie poster for The Slime People, a horror film directed by Robert Hutton, who also starred in the film. The film famously ran out of money nine days into filming and the cast finished the film wihtout getting paid. The film concerns a race of subterranean reptile-men (dubbed "slime people", due to their slime-covered skin) who create a wall of "solidified fog" around Los Angeles using a strange organic-looking machine and proceed to invade the city after they are driven out of their subterranean homes by underground atomic tests. I think you get the idea!
The film was infamous for its extensive use of fog machines, with the fog becoming so thick towards the end that it is virtually impossible to see any of the actors.