Have you ever started filming a movie you thought was a comedy, but it was actually a horror film? Probably not because, chances are, you're not a famous actor (but if it is you, Mr. Murray, humanity doesn't deserve you). But believe it or not, this kind of stuff actually does happen to movie stars. Actors who thought they were making different films (or at least, different kinds of films) are, well, people in Stephen King movies, mostly. And then there are actors whose roles were much different than they thought they'd be, including such big names as Charlton Heston, Halle Berry, and the whole freaking cast of The Usual Suspects.
It's surprising, but it happens more than you might think. Sure, actors could pay attention to what they're doing, or give a flying muffin about more than just a paycheck, but then we wouldn't have these hilarious stories. Here are some knee-slapping instances of actors coming out the back end of a film with no idea what the world was about to see.
Danny Lloyd played Danny Torrance in The Shining as a five-year-old. He also didn't know he was making a horror movie. This is mostly because he was told he wasn't, and children will believe chairs are spaghetti if you tell it to them with confidence.
Director Stanley Kubrick actually had the child's best interest at heart (which is shocking, given his well-documented insanity), so in order to protect little Danny from trauma, he not only told him they were making a drama, but he took steps to keep Danny out of scary situations. When Wendy is running from Jack with Danny in her arms, she's actually carrying a dummy, so the boy wouldn't have to be in a scary scene. That's borderline heartwarming!
The Thin Red Line is based on a novel about the Battle of Mount Austen, revolving around the character Corporal Fife (played by Adrien Brody in the movie). Brody made the reasonable assumption that he was the main character of the film, since Fife was the main character of the novel, but it turned out he was wrong.
Since he was an up-and-comer at the time, many of his scenes were cut from the final product, highlighting the real stars of the film George Clooney, John Travolta, Nick Nolte, John Cusack, Woody Harrelson, and Sean Penn, even though none of them were, you know, the protagonist. Brody, unfortunately, was unaware of the cuts, but learned when he viewed the premiere with his parents whom he had brought along, brimming with pride. And then, presumably, deflated with crippling sadness.
Frankie Laine was a singer who recorded music for a number of famous westerns like 3:10 to Yuma and Rawhide, so Mel Brooks thought he'd be a perfect fit for the theme of Blazing Saddles. Frankie Laine agreed to take the gig, and was so moved by his performance that he cried after recording it.
This is a strange reaction, considering the movie's a preposterous satire of the Western genre, but Laine apparently had no idea: "I thought I was doing a song for another High Noon, and I gave it my best dramatic reading ... When I saw wacky things happening on the screen, like a guy punching a horse, I sunk down into my seat with embarrassment."
Bryan Singer kept his entire cast in the dark on The Usual Suspects, so that going into the premiere, Gabriel Byrne, Benicio Del Toro, Stephen Baldwin, and Kevin Pollak all thought they were Keyser Soze. Byrne was so pissed, he apparently dragged Singer outside and screamed at him.
If he wasn't deserving of it then, it's at least punishment for a couple of bad X-Men movies, Superman Returns, Jack the Giant Slayer, and some other truly unsavory things he's rumored to have done.