This 1979 Italian cannibal horror film was not submitted to the BBFC at the time of its original production, presumably because no distributor felt that it was likely to be acceptable for classification at that time. Instead, a version of the film that had already been slightly pre-cut by its distributors was released on video in 1982 without a BBFC certificate. At the time there was no formal requirement that videos should be classified by the BBFC, with the result that a number of small and enterprising companies exploited the loophole by releasing strong horror films onto the video market without submitting them to the BBFC. Not only did the lack of video classification mean that material that had been cut or rejected by the BBFC (or which would not have been classified by the BBFC) was freely available, it also meant that such material was available to persons of all ages, including children.

It did not take long before the Press launched a campaign to ban unclassified horror cassettes, which were now being termed 'video nasties'. In response, the Director of Public Prosecutions drew up a list of videos that he believed were obscene under the terms of the Obscene Publications Act. Some of the 'video nasties' in fact turned out to be comparatively mild and a handful had even received BBFC cinema certificates. In a number of cases the sensationalist marketing of the films and their lurid packaging artwork was actually worse than the content of the films themselves. As a result, titles were periodically removed from the list as and when they were found 'Not Guilty' by the courts. However, there was a hard core of nasties that would certainly have posed major difficulties for the BBFC had they been submitted for classification. Cannibal Holocaust was one of the strongest titles on the list.

Cannibal Holocaust recounts the story of a film crew searching the South American jungles for a missing team of young documentary film-makers. Although they never find the missing crew members, they do uncover some camera equipment and unopened film cans. When the footage is returned to New York, a professor is hired by a TV broadcaster to help assemble the found footage. He swiftly discovers that the film crew were in fact frauds, illicitly fabricating footage by perpetrating atrocities on the local people and wildlife. As the film proceeds, we are shown the final footage shot by the missing crew as the local people take their terrible revenge.

Cannibal Holocaust was not formally submitted to the BBFC until 2001, largely because its reputation as a 'video nasty' and its long history of prosecutions for obscenity seemed to preclude the issuing of a BBFC certificate.

When it was submitted for video and DVD release the BBFC examined the film very carefully in terms of its own published Guidelines.

The film's presentation of strong sexual violence infringed the Board's strict policy on rape and sexual violence which states that 'Where the portrayal eroticises or endorses sexual assault, the Board is likely to require cuts at any classification level'. Furthermore, in common with a number of Italian films of the same period, the scenes of cruelty to animals were clearly unsimulated and deliberately orchestrated by the filmmakers. UK law prohibits the public exhibition of cinema films if animals were cruelly mistreated during their making and the BBFC applies this test also to videos and DVDs.

Nonetheless, the BBFC recognised that the film, although strong, could be made acceptable, subject to the removal of the above scenes. The distributor therefore agreed to make five minutes 44 seconds of cuts to remove unacceptable elements, after which the film was passed at 18 for video and DVD release. Cuts were required in eight individual scenes: four scenes of sexual violence and four scenes of animal killing.

In 2011, ten years after its previous examination, the BBFC was asked to take a second look at the film for DVD and BluRay release.  Whilst recognising that the film still retains its power to shock and offend, the Board concluded that the scenes of sexual violence that had been subject to reductions in 2001 no longer warranted cuts at the adult level.  Careful examination of the scenes in question showed there was limited detail of nudity and therefore little eroticisation. Furthermore, the scenes were often chaotically filmed, with hand held cameras, and/or featured frequent cutaways to the reactions of horrified onlookers.  Their likely effect was to horrify and disgust the audience, rather than to eroticise or endorse such activity in the real world. 

In terms of the scenes of animal killing, the BBFC concluded that one of the four scenes cut in 2001 still required intervention because it clearly showed an animal being made to suffer in a cruel fashion.  The killing in question, in which a small mammal has its neck cut with a knife, is quite protracted and the animal is seen to struggle and scream as it bleeds out.  However, careful inspection of the other previously cut scenes revealed that the animals in question were killed quickly and cleanly.  For example, the notorious scene in which a turtle is killed shows the turtle's neck being cut with a single rapid blow, instantly severing the spinal cord and killing the animal immediately.  These scenes were not, therefore, in breach of BBFC policy, which prohibits 'cruelty' to animals but not the killing of animals, providing that the killing is swift.  In each case, the animal's body is seen to twitch after death but this was considered to be a post mortem reaction, akin to a headless chicken running around a farmyard.  The BBFC recognises that some viewers may find the scenes of animal killing offensive or upsetting, not least because of the nervous reactions on display in the animals' bodies or body-parts after death.  However, the scenes do not breach the terms of BBFC policy, itself based on the Cinematograph Films (Animals) Act 1937.  It was acknowledged that the decision to cut these scenes in 2001 was primarily the result of the disgusting nature of the sequences, as well as the history of the film as a DPP-listed 'video nasty', rather than the result of a strict application of policy.  Removing these sequences would be inconsistent with the BBFC's decisions to permit quick clean kills in several other films, such as Apocalypse Now.

Accordingly, in 2011, Cannibal Holocaust was rated 18 after fifteen seconds of cuts to one scene of animal cruelty.  The BBFCinsight states that the film 'Contains strong sex, sexual violence, bloody violence, and animal slaughter'.