Behind the scenes of blockbuster movies like "Transformers," "The Matrix" and "Braveheart" is the foley stage -- a cluttered studio full of noisy knick-knacks and a soft-spoken woman named Mary Jo Lang.
Lang is one of the few female foley mixers in the world, recording sound effects created by foley artists and then mixing them to enhance a film's audio. The people who record sound on movie sets are primarily there to capture dialogue -- not buildings falling, or doors closing or silverware clinking.
There are more than 100 foley artists around the world concocting those sounds from their imaginations, and a mere 50 foley mixers who seamlessly work the sounds into the movies.
If they need to create the sound of galloping horses, toilet plungers will do the trick.
If someone in a movie is walking on leaves, a foley artist is behind the scenes, crunching up audio tape.
"For bones breaking, for example, celery is a big item," Lang said.
"And we do make sounds for things that don't make any sound," Lang said with a laugh. Animated movies have no sound except for dialogue, so every other sound you hear is thanks to foley artists and mixers.
Foley artists are named for sound editor Jack Foley, who created this art of sound more than 80 years ago.
"I Am Legend," "American Gangster" and the Oscar-winning "Schindler's List" are a few of the 100 movies mixed by Lang.
Lang said she was intrigued by sound even as a little girl, but she never dreamed her ear for detail would flourish into a Hollywood career as an award-winning member of the Academy of Arts and Sciences.
"I'm very proud of being a member of the academy, because I believe it's dedicated to the art of moviemaking. Movies are what books were in the turn of the century. They determine and reflect culture of the time. They are the commonality between people. And the ideas that you get in movies go all the way around the world," Lang said.
Lang travels around the world armed with a tape recorder to capture sounds from street noise in India to honking penguins in Antarctica.
"Working in foley and in sound in movies has really honed my thinking of sound as an emotional experience," she said.
Lang just finished mixing the new summer movie "Get Smart," and she's now working on "Speed Racer." Her next project will be the new Batman movie "Dark Knight," featuring the late Heath Ledger.