The comedic ensemble cast of Monsters Versus Aliens improvised their own lines - and even went back and forth over a period of years, redoing the same scenes, co-director Conrad Vernon told io9. Spoilers ahead...
In Monsters Versus Aliens, a woman named Susan gets hit by a meteor and becomes a bleach-blonde giant on her wedding day, so she's shipped off to a secret government facility where a host of classic monsters are kept. At the same time, a giant robot arrives from outer space to conquer the planet on behalf of the evil Gallaxhar. Conventional weapons are no use, so the government decides to send Susan and the other monsters to fight the alien menace.
Spooky improv at a distance:
The recording process for Monsters Versus Aliens sounded totally demented, the way Vernon described it. On the one hand, stars like Hugh Laurie, Will Arnett, Seth Rogen, Kiefer Sutherland, Stephen Colbert and Rainn Wilson were encouraged to make up their own dialogue and go crazy with the script. On the other hand, none of the actors were ever in the same room together - except for one scene between Reese Witherspoon (Ginormica) and Paul Rudd (Derek, her fiance).
"That's one reason we enlisted these great comedic actors: We needed the dialogue to sound completely natural, because this was an ensemble cast," explains Vernon. But at the same time, "they're never really together, in the sense of recording their dialogue together."
Instead, the actors were bouncing their dialogue off a "reader," named Stephen Kearin, and when they would ad lib, "he would come back at them" with an ad lib of his own.
So if Seth Rogen (B.O.B.) came up with a great line that wasn't in the script, the directors would go to Will Arnett and Hugh Laurie and tell them what Seth had said. And then Arnett and Laurie would make up their own responses. And then the tape would go to Reese Witherspoon. And often, it would end up coming back to Rogen a few more times, so he could respond to what the other actors had ad-libbed. And sometimes, Rogen would end up changing his original line of dialogue that had sparked all of this round-robin reinvention.
"It was very iterative," explains Vernon. The same scene would get re-recorded over and over, "more than several times."
The benefit of 3-D:
Since James Cameron told Time Magazine that proper 3-D movies use more neurons in your brain and create a "real" experience, I asked Vernon if the MvA audience might possibly think they were watching a documentary. He didn't seem to think so. But he did think that having the movie in 3-D made the sight gags pop more. And it allowed you to become more invested in the characters and "more on the edge of your seat when they're in danger."
Are classic science fiction films the new fairy tales?
Vernon directed Shrek 2, which plays with the classic Disney formula of making old fairy tales into animated source material. But now he's making a film that uses classic science fiction characters like the Blob, the 50-foot woman and the creature from the Black Lagoon in place of fairy-tale characters.
Vernon says he thinks these characters are "atomic-age fairy tales: each one of them has a certain idea behind it, and a certain moral, and a certain story theme." Many of the 1950s movies are about what happens if the bomb drops, and "what would be the fallout." So in a typical 1950s movie, "this was a fish that absorbed atomic radiation, and grew to be 1000 feet tall. And now it's flopping around New York eating everything." So whereas a fairy tale might have a moral about jealousy or talking to strangers, these 1950s movies have a moral about being careful with atomic weapons.
And Vernon definitely hopes MvA will appeal to adults who remember seeing these old monster movies on television. "It's like these characters kind of transcend time" and keep getting reinvented for new generations. Frankenstein has already been around since the 1800s and on film since the 1930s, but each generation makes its own Frankenstein story. "They're always going to have new generations becuase of the way they're updated. There was even a new Blob movie put out. We wanted the adults to remember those movies and know the movies and kind of nod to them. It's nostalgic and pulls at the heartstrings a little bit."
At the same time, Vernon would rather reinvent these old characters and ideas than do a straight-up remake. "You have to give everything a new spin," he says. "The original is always going to have more punch."
Yay for empowerment!
So what's the moral of Monsters Versus Aliens? Vernon says there are "parallel messages" going on at once. "I think the main message is for Susan (aka Ginormica), [and that is] 'Don't let anyone tell you what you can and can't do, and who you are. Be proud of who you are, and don't let anyone stop you doing what you want to do.'" And once Susan learns this lesson, she passes it on to the other monsters. She also learns not to let her weatherman fiance Derek treat her like dirt any more.