23 is a 1998 German drama thriller film about a young hacker Karl Koch, who died on 23 May 1989, a presumed suicide. It was directed by Hans-Christian Schmid, who also participated in screenwriting. The title derives from the protagonist's obsession with the number 23, a phenomenon often described as apophenia. Although the film was well received by critics and audiences, its accuracy has been vocally disputed by some witnesses to the real-life events on which it was based. Schmid subsequently co-authored a book that tells the story of the making of 23 and also details the differences between the movie and the actual events.

In 1980s Germany at the height of the Cold War, 19-year-old Karl Koch (August Diehl) finds the world around him threatening and chaotic. Inspired by the fictitious character Hagbard Celine (from Robert Anton Wilson and Robert Shea's Illuminatus! Trilogy), he starts investigating the backgrounds of political and economic power and discovers signs that make him believe in a worldwide conspiracy.

A film, also called a movie or motion picture, is a series of still or moving images. It is produced by recording photographic images with cameras, or by creating images using animation techniques or visual effects. The process of filmmaking has developed into an art form and industry.

Films are cultural artifacts created by specific cultures, which reflect those cultures, and, in turn, affect them. Film is considered to be an important art form, a source of popular entertainment and a powerful method for educating – or indoctrinating – citizens. The visual elements of cinema give motion pictures a universal power of communication. Some films have become popular worldwide attractions by using dubbing or subtitles that translate the dialogue into the language of the viewer.

Films are made up of a series of individual images called frames. When these images are shown rapidly in succession, a viewer has the illusion that motion is occurring. The viewer cannot see the flickering between frames due to an effect known as persistence of vision, whereby the eye retains a visual image for a fraction of a second after the source has been removed. Viewers perceive motion due to a psychological effect called beta movement.