The term "speculative fiction" is sometimes used to avoid making a distinction between various strands of fantasy, science fiction, and horror or to account for the considerable overlap among the three. While both science fiction and horror films are certainly types of fantasy, many would agree that each is distinct in its purview and that each operates differently in terms of themes, conflicts, and iconography.
Whereas science fiction relies on scientific paradigms, technologies, facts, and paraphernalia to create hypothetical but scientifically credible scenarios, fantasy is subject to no such restrictions. Fantasy does not need to convince the audience that its story is realistic—rather, it invites the audience to temporarily expand its credulity—hence the phrase so often associated with this genre, "the willing suspension of disbelief." Rather than appeal to science, fantasy favors magical or mystical explanations. Fantasy films are usually logically consistent, but their internal logic belongs to an imagined rather than a scientific world. Although the iconography of science fiction includes spaceships, computers, and ray-guns, a fantasy film is more likely to feature flying horses, crystal balls, or magic wands. In practice, however, many films are hybrids. For example, the science fiction film The Empire Strikes Back (1980) invokes no scientific premise to explain Yoda's mystical powers or Luke's mastery of the "the Force," a skill that defies logic and must be accessed through a kind of intuition. Likewise, E.T. the Extraterrestrial (1982) features an adorable alien whose ability to heal wounds seems more miraculous than medical.
While some science fiction films are dramatic or upbeat, many attempt to frighten the audience, thus blurring the line between science fiction and horror. Typically, the divide between pure horror and science fiction depends on the presence of scientific elements. Another distinguishing factor concerns the nature and the source of the horror: science fiction is more likely to be concerned with an external threat on a grand scale (for example, aliens attacking the Earth in War of the Worlds ), whereas horror is more likely to stem from internal, human evil on a more personal scale (for example, evil ghosts threatening a family in Poltergeist ). While some fantasies invoke horror and some horror films are clearly fantasies, films of terror that would not be considered fantasy include slasher films such as Friday the 13th (1980) or thrillers such as Dial M for Murder (1954), since in each case the source of fear is rooted in a (hypothetically) realistic threat. A science fiction film such as The Andromeda Strain (1971) may also provoke fear, thus overlapping with horror, but it too would be excluded from a pure fantasy classification because its horrific scenario is grounded in the logical conclusions to scientific hypotheses.
Horror films most often overlap with fantasy when they feature monsters or creatures with no clear scientific explanation (the frightening but misunderstood ape in the classic 1933 film, King Kong ), or when they enter the supernatural realm (ghosts, vampires, unexplained phenomena). What distinguishes supernatural horror from pure fantasy is the pervasive presence of a horrific and threatening scenario. Ghosts in films like A Guy Named Joe (1943) or Beetlejuice (1988) function very differently from ghosts in horror films like The Haunting (1963); the tone of the films differ accordingly.
Even though science fiction and horror blend with fantasy in many movies, many fantasy films fit neither of those categories and instead find their roots in fairy tales, myths and legends, comic strips, and children's stories. Excluding pure science fiction and horror, the major strands of fantasy might be grouped into the following general subcategories: sword and sorcery/medieval fantasy: Dragonslayer (1981), Willow (1988), The Lord of the Rings trilogy (2001–2003); children's stories: Peter Pan (1953), James and the Giant Peach (1996), the Harry Potter series (beginning in 2001); fairy tales and myths: La belle et la bête ( Beauty and the Beast , 1946), Jason and the Argonauts (1963); creatures and monsters: King Kong (1933), Monsters, Inc. (2001); supernatural: Here Comes Mr. Jordan (1941), Bedazzled (1967), Ghost (1990); magic or miracles: Big (1988), The Santa Clause (1994); comic book or superheroes: Dick Tracy (1990), Spider-Man (2002); romantic fantasy: Splash (1984), Groundhog Day (1993); comic fantasy: Beetlejuice (1988), Ghostbusters (1984); dream fantasy: The Wizard of Oz (1939); action fantasy: Raiders of the Lost Ark (1981); martial arts fantasy: The Matrix (1999), Wo hu cang long ( Crouching Tiger, Hidden Dragon , 2000); musical fantasy: Brigadoon (1954), The Lion King (1994); utopian fantasy: Lost Horizon (1937); dystopian fantasy: Brazil (1985); time travel: Time Bandits (1981), Bill and Ted's Excellent Adventure (1989); self-referential: 8½ (1963), Purple Rose of Cairo (1985), Pleasantville (1998); avant-garde or surreal: Le Sang d'un poète ( The Blood of a Poet , 1930).
These subcategories account for some of the major strands of fantasy, but they are by no means exhaustive, nor do they include such films as the delightfully warped Being John Malkovich (1999). Moreover, no matter how many highly particular categories are devised for fantasy films, many films nonetheless fit into a number of categories. The Princess Bride (1987), for example, is a romantic comedy but also a fairy tale; The Wizard of Oz (1939) is a musical but also a dream fantasy with a fairy-tale bent. A further distinction might be made between fantasies that are live-action ( Edward Scissorhands , 1990), animated ( Peter Pan ), puppet-based ( The Dark Crystal , 1982), or entirely computer-generated ( Toy Story , 1995). Here again, many films combine categories—for example, Mary Poppins (1964), which employs interludes of animation within a live-action setting, or the live-action/animated film, Who Framed Roger Rabbit? (1988), widely acclaimed for its innovative special effects.