The highest grossing Godzilla film of all time, this was originally Willis O'Brien's idea in the 1950s. He planned a King Kong sequel, pitting the ape against a giant Frankenstein creature. Producer John Beck sold the idea to Toho studios (reportedly against O'Brien's wishes), and this is the result.
Godzilla is resurrected from his icy tomb at the end of his previous film (Godzilla Raids Again), and Kong is captured by a pharmaceutical company looking for a new ad campaign. Each monster begins their own rampage (Kong does so after destroying the raft he was transported on), until the climatic battle begins to rage on the base of Mt. Fuji. The ending is the same in both the American and Japanese versions (regardless of popular belief), though the two films are completely different.
Most of the Japanese comedy would baffle American audience; so new scenes were shot for the US release, cutting down on the characterization and plot developments. It leaves the film in a butchered, confusing state, though most audiences simply came to the see the monsters. There is no stop motion animation this time, as two men in suits rumble around miniature sets.
The Kong suit is one of the hardest things to swallow for die-hard fans (though not as bad as the next sequel). A floppy mess, with arms that change in size from scene to scene and a mask that's easy to see through, this remains one of the worst incarnations of Kong to date. The fight is played for laughs, and that's how many people view the Godzilla series.