It's not easy distilling a two-hour movie into a two-minute trailer. It takes just the right balance between showing off the film's best qualities without giving away too much. Do it right, and you can hear a cinema audience buzz with anticipation. But a bad preview will guarantee they'll stay home opening weekend.
Here's our list of the five best and five worst trailers of the year. We're only including trailers for films released in 2011, so it doesn't include the great previews for next year's movies like "The Avengers," "Snow White and the Huntsman," and "Paranorman."
The "Harry Potter" series has been the most successful franchise in movie history, so it had to go out with a bang. The trailer for the final film starts with flashes back to the previous movies stretching back over a decade, then gives glimpses of the epic final battle. It all adds up to a trailer that's not only exciting but surprisingly emotional.
WORST: HAPPY FEET TWO
The first "Happy Feet" won the Academy Award for Best Animated Feature, so selling a sequel should've been easy. But this trailer is an incomprehensible mishmash of random scenes clumsily cut together with no sense of story. Supposedly dramatic moments have no meaning, comedic bits aren't funny at all, and the music is a absurd mix of pop songs ranging from "Mama Said Knock You Out" to "Popa-Oom-Mow-Mow."
One sign of a very effective trailer: by the end you're rooting for the human beings to lose. After Tim Burton's disappointing attempt to revamp "Planet of the Apes," this new origin story seemed like a big gamble, especially since all of the apes would be completely digital creations. But the trailer showed that not only was Andy Serkis's performance as the chimpanzee leader Caesar totally believable, but authentically touching.
Adam Sandler's production company Happy Madison was responsible for some terrible trailers this year: "Just Go With It," "The Zookeeper" and "Jack and Jill." But nothing could have been worse than "Bucky Larson." Nick Swardson plays the title character who comes off as so annoying in this preview it's hard to believe anyone would want to spend another 95 minutes watching him.
This trailer starts off by very slickly laying out the basics of the story: Ryan Gosling plays a movie stunt driver by day and criminal by night. We see the basic set-up for the plot and the action scenes. But halfway through, the electronic music is replaced by a slow, orchestral piece that serves as a counterpoint to the harsh violence we see on screen. It tells you quite clearly that this isn't going to be your standard action flick (though a woman in Michigan did file a lawsuit against the studio claiming the trailer was misleading).
WORST: THE DOUBLE
A retired CIA agent is brought back to active duty to hunt down the Russian assassin he was never able to catch. Sounds like it could be the set-up to an intriguing thriller, right? Well, maybe it might have been if they hadn't given away the big twist right in the trailer. Yes, the movie revealed who the spy was a half-hour into it, but spelling it out in the trailer just removes any possible motivation one might have for actually going to see it.
Director David Fincher had one of the best trailers (and films) of 2010 with "The Social Network," so cinephiles were anxiously awaiting to see if he could top it with his adaptation of Stieg Larsson's bestselling novel. The teaser trailer is a propulsive montage of quick cuts that are intriguing if you haven't read the book and revealing if you have. There's no sound other than Karen O's cover of Led Zepplin's "The Immigrant Song," which gets progressively louder as the trailer plays until it's almost deafening. And it ends with the best tagline of the year.
WORST: SHARK NIGHT 3D
How can a movie about sharks eating people look so boring? The trailer follows the most generic set-up imaginable: good-looking college kids go to a remote location for a getaway, then start getting picked off one by one. It even tries to shoehorn in an explanation as to why there would be sharks in a lake. But all of it is extremely unconvincing and unengaging. And it never explains why a movie called "Shark Night" seems to take place entirely during the day.
BEST: THE MUPPETS
The return of the Muppets to the big-screen this year was set up perfectly by a series of parody trailers poking fun at the very nature of trailers. They spoofed romantic comedies, "The Hangover" and "Green Lantern." But the best was their take on the aforementioned "Dragon Tattoo" trailer. It was clever and self-aware in just the right combination to appeal to the adults who grew up watching -- and had their senses of humor shaped by -- the Muppets.
WORST: KILLER ELITE
The action in this trailer is admittedly pretty good, especially the shot where Jason Statham flings himself out of a window and crashes down on a truck. But the dialogue featured every clichéd tough-guy line you could think of: "Game's over." "You have no idea who you're messing with." (Though "messing" was obviously dubbed over by someone who isn't Clive Owen.) "He's like a father to you." "He's your worst nightmare." "This ends today!" "Now the gloves are off!" "Let's finish this!" It's like every line was cut-and-pasted from another (and better) movie.