Harry and Michael Medved's The Fifty Worst Movies of All Time (1979) was one of the first popular books devoted to bad films. Their list of ‘wretched films’ and ‘embarrassing disasters’ covers everything from big-budget failures (like Lost Horizon [Charles Jarrott, 1973]) to pretentious art cinema (including Alain Resnais's Last Year at Marienbad [L’Année dernière à Marienbad, 1961]). The Medveds’ list also devotes space to ‘hackneyed and ridiculous film formulas’, noting that ‘no book on the worst films could be complete without a jungle movie, Japanese horror epic, a singing-cowboy saga, a violent blaxploitation films and a spaghetti Western’ (11). Their chosen kaijū film is Godzilla vs. the Smog Monster (Gojira tai Hedora, 1971).1 In their introduction, the Medveds mention that ‘foreign’ films are beyond the scope of their investigation, and that unreleased or low-budget cinemas make comparisons with Hollywood standards either impossible or unfair. The kaijū film is fair game, however, although the Medveds don't mention that the version they’re referencing was both altered and dubbed by AIP. The ‘immortal dialogue’ from the film was inserted by AIP, rather than using the international version provided by Tōhō. The kaijū film is dismissed as shlock: ‘To ensure consistent quality, each of [its] new creations was presented with atrocious acting, sloppy direction, farfetched scripts, execrable music, amateurish photography, laughable sets, and last but not least, ludicrous monsters’ (93). While Godzilla vs. Hedorah represents the intensifying crisis in the Japanese film industry at the time, many of the criticisms directed at the film are the result of the decisions of American distributors, who regularly transformed kaijū films, through dubbing, use of library music and re-editing. Many of these decisions helped transform the kaijū film into the ‘bad object’ of the Medveds’ book, as well as allowing the genre to become the subject of cult fascination. There are many sites and online articles, videos and podcasts devoted to documenting the changes made to kaijū films by global distributors, from inserting new English-speaking characters to retitling for release to fit with pre-existing content or properties. As I argue here, such changes played an instrumental role in turning examples of popular national cinema into global exploitation film.