In written fantasy, Monsters need not be huge; in the Cinema they almost always are, unless occurring en masse – as swarms of mutant bees, shoals of mutant piranhas, or mutant whatevers. On occasion they can start small and end up huge – as in the Alien series of sf movies, Arachnophobia (1990), etc. – but generally they are vast from the outset. Even Frankenstein's monster (> Frankenstein Movies), although made from the parts of presumably normal-sized human beings, is almost always depicted as larger than any normal man.
Dinosaurs and Apes are the most popular monsters, the former typified by the Godzilla Movies – although The Lost World (1925) really started the trend – and the latter by the King Kong Movies, which had spinoffs like Mighty Joe Young (1949). Prehistoric Fantasies, like One Million Bc and its various spinoffs, normally see humans battling, however implausibly, with giant creatures; The Clan of the Cave Bear (1985) is a glorious exception. The taxonomy of the eponym of The Creature from the Black Lagoon (1954) is unclear, although it is to be assumed that he (or she or it) is an amphibian.
More interesting are instances where humans become monsters. This happens to the protagonists of the various Fly movies but perhaps more importantly to the denizens of the Wainscot society at the heart of Nightbreed (1990). Vampires, werewolves and zombies (> Vampire Movies; Werewolf Movies; Zombie Movies) are all in their diverse ways humans monstrously transformed. The cinema has not generally dealt very well with such iconographic characters: to take a single example, Lawrence Talbot, the werewolf protagonist of The Wolf Man (1941), within only a few years found himself in the debasing Abbott and Costello Meet Frankenstein (1948). The general trend of Hollywood to discover an Icon and then swiftly degrade it is nowhere more evident than in the case of monster movies. [JG]