BACKGROUND Tobacco promotion is now tightly restricted in the UK and many other countries, but tobacco imagery including brand appearances in the media remain potentially powerful drivers of smoking uptake among children and young people. The extent to which tobacco imagery and specific products have appeared in the most popular films viewed in the UK over 20 years has been measured, in relation to year of release, the age certification allocated to the film by the British Board of Film Classification (BBFC), country of origin and other characteristics. METHODS Occurrence of tobacco intervals (tobacco use, implied use or appearance of smoking paraphernalia) and brand appearances were measured by 5 min interval coding in the 15 most commercially successful films in the UK each year from 1989 to 2008. RESULTS Tobacco intervals occurred in 70% of all films. Over half (56%) of those that contained tobacco intervals were rated by the BBFC as suitable for viewing by children aged <15, and 92% for people aged <18. Tobacco interval appearances fell by approximately 80% over the study period, but persisted in films in all BBFC categories. Brand appearances were nearly twice as likely to occur in films originating wholly or in part from the UK (UK films). Specific brands, particularly Marlboro and Silk Cut, appeared in 9% of all films, and most brand appearances (39%) were in films with BBFC 15 classification. CONCLUSIONS Tobacco imagery in the most popular films shown in the UK has declined substantially over the past 20 years but continues to occur, particularly in UK films, and predominantly in films categorised as suitable for viewing by children and young people. Specific brand appearances are now rare but occur repeatedly in some films. The BBFC is not currently protecting children and young people from exposure to tobacco imagery in film.