1930s -- fiction
The most famed and prolific area of science fiction is the planetary adventure, featuring strange environments, exotic alien races, and massive battle scenes. Many of the most popular science fiction universes, such as Star Wars, Star Trek, and Avatar, take place in these environments. Most of these universes owe their existence to the adventure fiction of one author.
One of the sub-genres that defined classic American crime and detective movies was film noir, a style that was pervasive in detective films of the 1940s and 1950s. Film noir arose during the post-World War II period in the United States as a generation that fought in one of the most brutal conflicts the world had ever seen returned home to a changed America where jobs were scarce and the national mood seemed darker and more cynical than during the war itself.