I'm not going to see "Spider-Man: Homecoming" this July. You're probably thinking I'm one of those anti-Marvel snobs who calls movies "films" and refers to foreign films by their non-English titles. It's not that. It's that I basically saw the whole movie already, when I caught the trailer before watching "Guardians of the Galaxy: Vol. 2."

It's not just "Spider-Man." Last year, one "Star Trek: Beyond" TV spot centered on the fact that the villain Krall was actually a human (a late-movie twist).

Our increasing obsession with trailers is changing how we watch movies. We're becoming audiences afraid of surprise, audiences that would rather watch movies we're certain we'll like than risk watching films that surprise us into love. In some cases, this fixation is even lowering the quality of movies themselves by encouraging bad filmmaking habits.

The most extreme example happened when Warner Bros. released such a successful trailer for "Suicide Squad" it brought on the company that cut it to edit the whole film -- dropping the director's original cut altogether.

Marvel Studios

But haven't trailers been around for, like, forever?

It's true: The first movie trailer aired in 1917. For decades, trailers included text or voiceovers that read like the back of books. But in the '60s, something changed. Filmmakers like Stanley Kubrick began cutting the first montage trailers, which relied only on film from the movie itself.

Montage trailers meant filmmakers could give a truer sense of the spirit of their movies, rather than just telling viewers what the basic concepts or conflicts were. This method posed a major question, though: which footage could you show without revealing too much?

Flash-forward to the modern film industry and that question has exploded. Thanks to trailers' easy accessibility on YouTube and those shot-by-shot breakdowns that quickly appear online once trailers drop, anyone interested in a given flick can pore over all the available footage for hours -- even if that leads to major spoilers for them and everyone they share it with.

To be fair, trailers themselves aren't helping.

Let's go back to "Spider-Man." The newest trailer gives the whole plot (and most of the characters): cheeky high schooler Peter Parker (Tom Holland) dresses up and fights crime. Tony Stark (Robert Downey Jr.), who gave him the high tech costume to begin with, warns him not to bite off more than he can chew.

Enter Michael Keaton reprising his role as Birdman (or the unexpected Vulture of ignorance), a working-class villain who hates corporate innovators like Stark. Spider-Man fights the Vulture, leading to near-casualties. Stark takes away his costume because the teen hero (surprise!) bit off more than he could chew.

The best way to encourage movie studios to make better trailers (and by extension, better movies) is to support the good ones.

But then things get personal, and the kid dons his original makeshift costume to defeat Keaton. Toss in clips of a funny best friend in on the secret and a girlfriend who must be kept in the dark (why? who cares?), and you've got the whole movie in less than three minutes. The only thing missing is the final scene where Stark (as surrogate father) realizes Parker has grown into a man and gives his suit back with a "Welcome to the Avengers, kid."

The "Spider-Man" trailer isn't the worst offender, but it seems the montage trailer has started falling into the trap it was built to avoid in the first place: just telling viewers exactly what's going to happen in the movie.

But do bad trailers really affect movies themselves?

OK, so some bad trailers are spoiling movies. But that doesn't mean the movies themselves are bad, right? Just look at all the examples of trailers that undersell brilliant movies. The problem comes when we desire familiarity more than anything else, because movie studios will give it to us.

Alcon Entertainment

Few big-budget movies will surprise you this year. Most are comic adaptations ("Spider-Man," "Thor: Ragnarok," "Guardians"), sequels to old favorites ("Blade Runner 2049," "Alien: Covenant," Star Wars) or other series entries (MCU, DCEU, MonsterVerse).

I'm not saying every adaptation or sequel is bad. Some, like "Guardians of the Galaxy" or "Mad Max: Fury Road," draw viewers with the familiar and still manage to offer some originality. But more often they're so concerned with recapturing the magic of their source material (or in the case of "Suicide Squad," recapturing the magic of their trailer) that they miss what made the originals so magical to begin with: they were unencumbered by audience expectations.

Is there a solution?

The best way to encourage movie studios to make better trailers (and by extension, better movies) is to support the good ones. One recent ad campaign, for instance, flips the old model of montage trailers on its head. The trailers for the Stephen King adaptation of "It" have barely shown the clown, Pennywise, or many major plot points. Instead, each one has focused primarily on a single early scene -- giving a sense of the characters and the tone of the story without giving away the larger story itself.

I love this approach, even though -- and maybe precisely because -- it means I won't be able to anticipate every story beat in the movie five minutes ahead of time. Of course, that might mean "It" sorely disappoints me. But like the original "Star Wars," or "Blade Runner" or "Alien" or any other movie that expanded what I thought images on a screen could accomplish, "It" might surprise me. And at this point, I'll take the risk of "It" over the certainty of "Spider-Man" every time.

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