A mockumentary is a "mock documentary", a parody of the often earnest nature of the documentary film genre. Although the term mockumentary didn't enter pop culture until the release of Rob Reiner's groundbreaking comedy This is Spinal Tap, many filmmakers over the years have created fictionalized documentaries and false newsreel footage for comedic effect.
One such early mockumentary carefully detailed the harvesting of spaghetti from a grove of fictional spaghetti trees. Another short mockumentary demonstrated a miraculous dry-cleaning process in which customers simply walked through a tank of fluid. The footage of users emerging completely dry and clean was actually filmed in reverse. The British comedy team Monty Python was notorious for creating full-length mockumentaries on fictional sports competitions or obscure historical figures.
The mockumentary film genre reached mainstream audiences first with director Rob Reiner's brilliant but fictional documentary about a British rock band called Spinal Tap. The band had obviously passed its prime by the time filming began, but an intrepid interviewer (Reiner) continued to explore the backstage world of the musicians, completely unaware of their rapidly fading fame. Separate, and largely improvised, interviews with the band members slowly reveal the sad truth behind their onstage personas.
A mockumentary is most successful when the structure of a traditional documentary is maintained or exaggerated. Interviews in a mockumentary are deliberately tiresome, with the interviewer's reaction shots obviously edited at a later date. The camera crew inevitably films moments best left on the cutting room floor, such as embarrassing conversations or completely self-indulgent interviews. The legitimate documentary style called cinema verite, using a hidden handheld camera to capture raw moments, is used extensively in a mockumentary for comedic effect.
Another hallmark of the mockumentary is the ironic juxtaposition of reality and the characters' skewed perceptions of that reality. Even as a film director in a mockumentary describes a peaceful and productive day on the set, the camera captures fist fights, walk-offs and slamming doors in the background. In a mockumentary, the characters' interviews and observations rarely agree with the chaotic reality captured by the cameras.
The appeal of a mockumentary lies in the alternative universe it creates. The audience knows the work as a whole is fictional, but there is little of the standard set-up and punchline formula found in traditional comedies. The humor in a mockumentary often arises from incidental bits of dialogue or visuals, accompanied by a talented actor's deadpan delivery of improvised lines. Knowledge of the documentary styles parodied in the film also helps explain some of the more arcane references. Many mockumentaries are rated very highly in critics' lists of best comedy films.