All movies must follow criteria that typifies them into a specific genre of film. For example, a romantic movie must create a chemistry between two characters. A good suspense movie must include a plot with several twists and turns in it. There are three criteria that can be used to judge whether or not a particular movie is a good science fiction film. These criteria include: a source of conflict; beleivable characters, images, and story; and well developed, visually appealing special effects. The movie Blade Runner has traditionally been categorized as a science fiction movie. It can be categorized as such because it does indeed follow the specified criteria.
In order to see exactly how Blade Runner follows the criteria of a science fiction movie feel free to browse: