The movie industry is now facing the same challenge the music recording industry has been dealing with for a long time: piracy. The illegal copying and distribution of music CDs is blamed for causing a sharp drop in retail sales as well as the loss of thousands of recording company jobs. So the film industry is taking steps to keep the same thing from happening to them.

"When we go to screenings now in Los Angeles, they wand you, frisk you and check your bag. They're very serious about it," explained film historian and critic Leonard Maltin. "At one screening, a friend of mine noticed they were [using] night-vision video cameras to scan the audience to see if they could [detect] anyone holding a [recording] device."

All of these security precautions have been imposed because people are, in effect, stealing movies according to New York Times film critic Elvis Mitchell.

"[If] something costs you $80 million, you're not exactly hoping someone will come along and steal it," he said. "It's a collaboration of a bunch of people and it's a component in the machine that keeps the studio running."

A machine that also keeps a lot of people employed. And these days, audiences are reminded of that just about every time they go to the movies. Before the feature begins, short filmed announcements are shown. They feature people who work behind the cameras, from lighting crews to make-up artists, who tell the audience how film piracy is affecting their work and lives.

Such pleas are aimed at discouraging people from engaging in the many ways films can and are being pirated. Saul Zaenz is a Hollywood producer.

"There's physical piracy where there are factories actually [making] and buying the stuff," said Saul Zaenz. "And they have some cases where they've caught guys with cameras inside theaters making bad copies and then selling them on the street for a few dollars. Then there's the piracy on the Internet, which is much more complicated."

And complicating things further, according to New York Times film critic Elvis Mitchell are conflicting copyright laws.

"It's not even based just in the United States anymore," he said. "The copyright laws are different from country to country. Because of these problems internationally and the advances in technology, it gets that much tougher to fight it all the time."

This fight is similar to the legal battle that have long been raging over intellectual property: who owns the right to a research paper, a piece of music, or a movie? Mr. Mitchell says film studios have to protect those rights as well as their financial interests.

"It's a filmmaker's legacy, but it's also the way studios keep themselves going with the library value of these movies," said Mr. Mitchell. "They count on the after-market to be as big a profit machine as the release of the movies theatrically."

But it's not only the film company profits that are at risk. Elvis Mitchell says actors and directors want their movies to be seen at their best, as they were intended to be seen.

"[In] the crappy versions that people pirate, you can see heads of people in the theaters walking, and hear people talking during the movie," he said.

Not everyone agrees, however, that all types of copying movies amounts to piracy, even veteran producer Saul Zaenz, who's made several hit films. "I don't think they should stop anyone from making a copy at home for themselves or to give it to someone as a present," said Mr. Mitchell. "I don't think anyone would complain if it's just done for personal use."

And there's the question of old movies that collect dust and sometimes deteriorate in studio vaults. Would pirating these films in order to keep them before the public really be a crime?

"The Founding Fathers believed in public domain," said broadcast critic Leonard Maltin. "They felt that, after a certain time, no one should own it, the public should own it. Now, in our corporate era, [studios] are saying, 'No, we've invested in it, taken care of it all this time, so we should own it longer.' But if they own it longer, they should also do something for the public, the public good."

Right now, though, the film companies are more focused on protecting their latest movies. And it's an enormous task. Industry analysts estimate that every day, about half a million movies are illegally swapped on the Internet alone.