How impressive a trailer is can make or break a film.
Trailers like Snow White and the Huntsman are, quite frankly, amazing. Trailers such as the one for Miley Cyrus's new film LOL, are not amazing. They are very, very bad. (No doubt because the films are very, very bad.)
What makes a trailer good is down to a lot of things: sounds, which clips are used, etc. But the main element of what makes a quality trailer is the editing. And as a testament to the power of editing, countless smartasses on the internet have re-cut and re-edited trailers for films to make them look like completely different films - the most disturbing examples of this are romantic comedies or family classics that have been made to look scarier than The Exorcist.
Here are a few of my favorite examples of film trailers being re-cut to look like horror films! (Just a warning, these will freak you the 'eff out.)
The Lion King
I'm not going to lie, this scared the absolute shit out of me. There's something deeply disturbing about a psycho, animated lion. I know I'm not alone in thinking this.
Mrs Doubtfire
If you think about it, having your dad dress up in drag to spend more time with you unsettling. Creative. Kind of touching. But mostly unsettling.
Sleepless in Seattle
Yet another incredibly creepy film if you really think about it. Meg Ryan is a full on stalker in this film, but somehow she makes it seem endearing.
The Sound of Music
To be honest, there are parts of The Sound of Music that I find quite scary, anyway. Like having a controlling father named Georg. Or accidentally falling in love with a Nazi. But this trailer is just too much.
Jane Eyre
If you've read this book, you know there are some properly scary bits in it, but this trailer is positively terrifying. I'll never walk around the house in the middle of the night with a lit candle again. *goosebumps*
Mean Girls
Obviously, mean girls in high school are enough to bring a grown man to tears anyway, but this cut of the trailer is chilling. (Also, it's so sad. Lindsay Lohan, what have you done to yourself!)
Honorable mentions include the original Scary Mary trailer, as well as this horror trailer of Titanic, which makes cold water flooding a hallway almost as scary as clowns.