The online video touted an epic unveiling from one of Hollywood’s most revered filmmakers: “In three days, Ridley Scott returns to the genre he redefined ...”

For the next two days, subsequent videos ratcheted up the excitement for the new project from the director of Alien.

Then, finally, it arrived: not the movie, not even the full-length trailer, but the one-minute “teaser” for Scott’s upcoming 20th Century Fox release Prometheus.

“We teased the teaser,” Fox chief marketing officer Oren Aviv said. “And it was viewed 29.7 million times.”

This is the new world of trailers, in which the Internet and rabid fan culture have turned one- to three-minute ads, once seen only in theatres, into events promoted and analyzed as avidly as the films themselves.

Trailers are now watched more online than in theatres, and in record numbers. Audiences streamed more than 5.3 billion trailers worldwide last year and are on track to significantly outpace that figure in 2012.

“Our work used to be looked at as pieces of advertising that quickly comes and goes, but now it’s a key piece of content that people are going to analyze and judge,” said Michael McIntyre, president of West L.A. entertainment marketing firm Mocean, which has made trailers for films including The Avengers, Project X and The Grey.

Aiming to take advantage of the mania surrounding material that they used to just hope people would remember after leaving the theatre, studios now market the marketing. Movies that followed Prometheus lead with a “trailer for the trailer” have included The Twilight Saga: Breaking Dawn — Part 2 and Total Recall, and Sony Pictures held screenings in 13 cities around the world in February to debut a trailer for The Amazing Spider-Man.

Yahoo, AOL and Apple’s iTunes battle to be the “exclusive” first home for a trailer online, often trading high-profile placement on a home page in exchange for the favour. In other cases, trailers are shared first with devoted fans via a Twitter feed or a Facebook game. Sometimes studios pay hundreds of thousands of dollars to companies that promise to help turn videos viral.

“You used to put the trailer in theatres and hope for the best, but now we can use digital marketing tools to make it a destination,” said Marc Weinstock, Sony worldwide marketing president.

First used nearly 100 years ago, when they were shown after the main feature, trailers long consisted of several scenes from a film interspersed with text or narration. Eventually they evolved, and now they feature super-fast cuts, flashy graphics and original soundtracks.

Studios typically spend between $100,000 and $200,000 to make each one, though the costs can rise as high as $1 million if the trailer includes an expensive song.

Several dozen companies in Los Angeles produce trailers, commercials and other marketing materials. Some have been around for decades and employ hundreds; others are boutique startups with just a few people and editing software. Nearly all pride themselves on making some of the most creative material coming out of Hollywood.

“When I started, there were a lot of people who might work on trailers in between editing movies,” said McIntyre, whose funky office is decorated with old licence plates, robot dolls and bowling pins. “Nowadays, 90 per cent of the people just love movie trailers.”

A key reason, professionals say, is the Internet.

“Our work has never been more popular, and that’s a great thing,” said Markus Werning, a trailer editor at Mojo in Los Angeles’ mid-Wilshire area whose recent work includes The Hunger Games. “We have the only job in the business where one person is truly his own filmmaker.”

To keep fans engaged and take advantage of the Web’s endless inventory, studios now put practically every available piece of content — be it trailer, commercial, clip or behind-the-scenes feature — online. Some produce online exclusives such as “red band” R-rated trailers, which usually feature outrageous content and require users to verify they are 17 or older in order to watch.

“We get so many more assets, and they’re rolled out earlier and earlier,” said Sybil Goldman, vice-president of entertainment for Yahoo.

The increasing numbers of trailers online and commentary surrounding them mean increased scrutiny for the people who make them. Bloggers and tweeters dissect every frame of a trailer for mysterious projects like The Hunger Games or Prometheus and can create instantaneous bad buzz for films whose trailers they don’t like, as happened to the flops John Carter and Green Lantern.

“People have access to so much marketing content in so many ways now that you have a higher bar for what is and isn’t a good trailer,” Aviv said.

There’s also growing scrutiny of the campaigns themselves. Avid fans are aware of the huge amounts of content being thrown at them and are becoming increasingly cynical.

“The general consensus among people I know is that they are milking it too much with a trailer for a trailer,” said Nick Bosworth, editor of the trailers section — yes, they have one — on the movie fan site JoBlo.com.

Some critics also complain that trailers too often give away the entire plot of a film. But testing shows that when they don’t know what to expect, moviegoers are less likely to buy a ticket.

Studios, in other words, are sticking with what works. As the hype, attention and attendant anxiety around trailer debuts keep growing, they increasingly resemble another high-stakes moment for the movie industry.

“In some cases,” said Mojo co-owner Michael Kahane, “the trailer launch has become just as big an event as the movie opening weekend.”