Semidocumentary is a form of book, film, or television program presenting a fictional story that incorporates many factual details or actual events, or which is presented in a manner similar to a documentary. Stylistically, it has certain similarities to Italian Neorealism, such as the use of location shooting and employing non-actors in secondary roles.
One of the first films of this kind was The House on 92nd Street (1945): Time used the term "semidocumentary" to describe this film in 1952 [1]. The producer of the film had previously worked on newsreels which inspired the film-making style.
In the late 1940s, semidocumentary films were often associated with film noir thrillers, sharing a commitment to on-location shooting, gritty realism, and understated performances. Several of Richard Fleischer's films had semidocumentary qualities; see external links below.
Some examples of movies that at least have some elements of a semidocumentary in their style: