(last updated 3 July 2007)

The term "movie trailer" refers to all the material that film distributors attach to the front of the movie reel: commercials, film previews, sometimes even PSAs. But over time, the term has become synonymous with previews of coming attractions.

Since these are essentially commercials for movies, for the studios the criterion for a great trailer is easy: it's whatever makes people want to see the movie enough to do so...particularly if they do so opening weekend. The "opening weekend gross" and the "opening weekend per-screen average gross" are used to determine both how successful a film is and also how many theaters will continue showing the film after the first week (yes, this is sort of a bad feedback loop). So, for the studios, great trailers are the trailers for the movies that do big business on opening weekend.

Logically, we can see that this is utter nonsense - a movie can perform well or completely flop regardless of the trailer. I think that, as viewers, we can also tell whether a movie is going to be good or bad regardless of the trailer. Therefore, if a trailer can be good or bad completely independent of the quality of the film, the trailer can and should be considered on its own merits, not only for its ability to get us to see the feature-length film it advertises, but also as entertainment in its own right. So what then makes for a good trailer for us, the audience? Here's some things I like to see in a trailer. It's rare that a trailer has all of these, but each one is a plus for any trailer in which they appear.

1. Good music
Trailers are short films - they're usually two minutes or less, and they have a definite, linear progression like any other film. Because they are so short, the potential for good sound design to influence the audience is much larger than for a feature length film. Since songs also have their beginnings, middles and ends, they are particularly well-suited, as most popular songs are not much longer than the trailer itself and can be easily edited down (removing refrains, etc) A good song can really pull all the disparate snippets of scenes together into one cohesive whole. I went to see Ringo Lam's "Maximum Risk" entirely based on the strength of link, even though it was a Jean-Claude Van Damme movie and I'd routinely panned his films when I'd worked as a movie reviewer.

2. Good pacing
Trailers - even trailers without good music - are better for being designed like little films, building to one or more "beats". Often these can lead to a climax, but the individual beats are more important. Particularly for action or adventure movies (but also for comedies), the trailer should quickly get us up to speed/level of excitement about the film, and then can spend the rest of the trailer maintaining that excitement. The link or the link are good examples of pacing. In the first, the build is a slow one, up until the moment the X-Wing comes tearing out of the TV screen to fill the theater, and in the second, the trailer has us thinking that it's a very different movie until the helicopter is caught in the webbing.

3. It should NOT tell the plot of the film
This one cannot be stressed enough - a trailer should get you interested in seeing the film without showing you the whole film. Bad trailers - such as link - show you the majority of the film you might see, with plot points in the order they are in the film, so that there is no surprise and nothing to look forward to when/if you actually see the film. Good trailers either show you footage from the film in an order where the plot progression isn't readily apparent (for example, link), or forgo film footage for scenes/shots that aren't actually in the film (the "Spider-man" trailer mentioned earlier). High on any list of the best film trailers ever is the original trailer for the Robin Williams movie "Toys" - it didn't show you anything about the film's plot; all it did was give an impression of the film as something whimsical with Robin Williams in it that involved toys. Such trailers make the audience curious about a film without giving anything away, which inclines me at least to see another film from the same director/studio/actors the next time.

4. A clear vision
Good trailers must clearly communicate some essence of the film they advertise. A bad trailer will be "all over the place": trying to do too much, either by making the film into multiple genres (A comedy! A drama! A love story! An adventure!) or by cramming simply too many characters/too much information into the trailer (see link for an example). Like a good music video, a trailer should have one primary concept/idea it is trying to convey. Any more than that and the message gets muddled.

Bad trailers are the ones the violate any of these: they have bad music, bad pacing, unclear concept and/or they tell the story of the film. Usually I will decide whether or not to see a film separate from consideration of the trailer, because there are so few good ones, but a bad one can make me give up on a film or, at best, wait for video (usually only when I've heard a lot of good stuff from people I respect - bad trailers have that much power!)

A good trailer, on the other hand, can make me more excited about a film. Sometimes, through trailers, I get interested in a film I might not know about otherwise, and other times the trailer will just renew and refresh my interest in a film I was already considering watching, "moving it up" in the ranking of films I want to or plan to see in the theater.

The ideal trailer has all of these: good music, a clear vision, good pacing, and doesn't tell the story of the movie. For a trailer like that, I will always go see the film.