Highly anticipated horror film The Cabin in the Woods comes out on Friday in the UK, but some may feel the trailers have given away a little too much. So are today's teasers getting a bit over-explanatory?

(Spoiler alert: Key plot details revealed below)

Trailers are meant to provide tantalising teasers to lure audiences in. But these days many seem to offer major plot twists.

One trailer for The Cabin in the Woods kicks off with scenes of a hawk slamming into some kind of force field and men monitoring their young victims from a control room. The shots divulge a key detail - that the movie is not a typical wrong-turn thriller, but a sci-fi "metanarrative" with a Truman Show twist.

Another trailer goes even further, strongly implying which two of the five central cast members survive at least until the final section of the movie.

But The Cabin in the Woods is far from the first trailer to show too much for some moviegoers.

In 2000, Cast Away, starring Tom Hanks as a stranded plane-crash survivor, gave viewers a glimpse of the final scene in its trailer - where Hanks returns home. Viewers could rest assured before even setting foot in a cinema that Hanks would make it off the island.

Image caption The Cabin in the Woods is marketed as a new type of horror flick

Audiences of the trailer for What Lies Beneath (2000) only have to wait two minutes to learn the identity of the ghost haunting Michelle Pfeiffer. It's the woman from her husband's affair.

And the trailer for Terminator Salvation (2009) didn't spare the identity of Sam Worthington's mysterious character. He's a terminator.

The trailer for Barney's Version (2010) takes viewers through all three of his wives, and even airs a pivotal scene where Barney meets the love of his life during his second wedding. She's not the bride.

Most recently, movie fans took to blogs and forums to decry the spoilerific Dream House (2011) trailer, which reveals two major turning points. Main character Daniel Craig is both the asylum patient and the murder suspect for his family's deaths. And he's innocent.

Critics' picks: Best trailers Seven: "It misleads you about what the film is. It makes it look almost Lethal Weaponesque and not in any way like what you're actually in for." - Helen O'Hara, Empire editor Inception: "From the trailer you knew it was going to be spectacular, but you didn't know it was going to be a movie for your brain as well." - James King, film critic "The trailer for that was brilliant, absolutely superb because it didn't actually tell you anything about the film, but it completely piqued your interest." - Xan Brooks, film critic Alien: "I had no reason to suspect that the entire cast wouldn't be killed off in the first scene, which made it a must see." - Fiona Cole, trailer producer Trainspotting: "I remember thinking when I first saw it, 'I totally, absolutely have to see that film immediately." - Cole Men rule movie trailers

In recent years the movie industry has shifted towards sharing more and withholding less, according to film critic James King. "More and more they are now showing the better bits in the trailer and the twists because they don't want to risk people being indifferent to it.

"In my job you always wonder about what you can say, how far can you go. My rule of thumb is if it's in the trailer, then I'm allowed to say it. I actually get quite a lot of leeway," he says.

Audience opinions about revealing trailers are mixed. Movie blogs and forums are littered with comments lamenting over-explanatory trailers that spoil the whole experience, but other moviegoers say they appreciate knowing what they're getting into.

User posts on CinemaBlend.com for the 2012 The Cabin in the Woods trailer are telling.

Commenter Zee finds the sci-fi scenes "a bit spoilerish", and says he would have been better off "skipping the trailer altogether". Whereas, Raul M writes: "Honestly, if they didn't reveal what they revealed in the trailer, I wouldn't have been interested in seeing the movie in the first place."

Image caption A character's terminator identity is revealed in the Terminator Salvation trailer

Offering audiences everything upfront can backfire, according to Xan Brooks, a Guardian film critic, who rarely watches trailers before screenings. "I'm always kind of stunned at how it's almost like a little abridged version of the film," he says.

"I'd be absolutely incensed to sit down and basically see the same thing I'd seen on the trailer but just kind of cranked out to two hours."

For producers the divide between divulging too much and not enough is a "fine line", says Fiona Cole, a freelance trailer producer.

"You have to show the jeopardy so that the audience will 'need' the resolution, but the second you've shown too much, the audience disengages," she says.

The ailing economy and pricey cinema seats also encourage oversharing trailers. Movie marketers must work harder to get audiences in the door, and viewers increasingly rely on trailers to decide which movies are worth their money.

Trailer trivia Trailers originally followed films - hence the name

Trailers started in 1912 as black cards with white text

Film critic Gene Siskel famously hated them

No longer just ads, trailers attract millions of viewers

Trailers can cost more than £600,000 to produce

Audiences watched more than 5.3 billion trailers worldwide in 2011 Source: IFC Entertainment and Los Angeles Times

"It's expensive to go to the cinema - you don't want to take a risk on something that you're a bit uncertain about," King says.

Helen O'Hara, an editor at Empire, says a similar aversion to risk may have compelled The Cabin in the Woods team to include the sci-fi tip-off in the trailer.

"The problem is that this is such an unconventional horror movie, they were worried people would feel misled if they didn't give you any hint of that in the trailers," she says.

For Cole, there's no excuse for over-explanatory trailers. Those that give away the game are "lazy" and fail to achieve their purpose - to inspire audiences. "It's maddening. I feel myself muttering 'stop now, stop now' before the trailer just about wraps the whole thing up for us," she says.

The internet has also pushed the scales toward revealing more about movies. Now filmgoers can click through their choice of trailers, teasers, TV spots, interactive websites and pictures online.

"Marketers have to be very careful that you can't basically build up a quilt of the entire film from all of those sources," O'Hara says.

If trailers fall flat, it's not for lack of effort. Trailers have evolved from short clips to mega marketing campaigns that generate their own waves of excitement, according to King. "Now the art of making a trailer is almost as complex as the art of making a feature," he says.

And there's nothing accidental about it. "The style they choose is deliberate. What they highlight is deliberate, and if they give away plot points or if they give away special effects, there's a lot of money making sure that that's in there as planned," he says.

Fans of the Cabin in the Woods trailer say the sci-fi scenes attract new viewers and don't spoil later surprises.

"The trailer does a great job of letting people know it's more than just a stereotypical slasher movie, without giving away the twists and ending (which is really awesome)," writes IMDB message board commenter Horrorwatcher. But he still cautions audiences to "stay away from any other trailers that might come out".

For O'Hara The Cabin in the Woods trailer "doesn't go the whole way" but could have held more back.

"There's still a load of stuff that isn't in the trailer, but it certainly gives away more than I consider completely optimal," she says.