The Dark Knight takes on the movie pirates

The Dark Knight, the latest Batman movie, is clearly a monster hit. The film could even end up besting all-time box office champ Titanic, which took a total of $600.8m. The question is why? Some believe the untimely death of Heath Ledger, who plays the Joker, helped excite tremendous interest in the film. Others believe the film's dark themes reflect the bleak economic and political mood of the times.

But there's an even more intriguing possibility - a highly secretive, six-month, multi-million dollar anti-piracy operation launched by Warner Bros. The studio was determined to prevent pirated copies of The Dark Knight from hitting file-sharing services on the internet before its cinema release. Batman's most likely audience - young men - is the demographic most likely to download pirated films.

These days some pirated movies are available on the internet and street corners across the world weeks before films are released. The major Hollywood studios claim to lose a combined total of over $6bn a year from such piracy. Films can be pirated from copies smuggled out of post-production companies where the film is edited, the sound track is created or by recording preview screenings on camcorders surreptitiously taken into cinemas.

So Warner took a number of unprecedented precautions with The Dark Knight, which had cost them $180 million to make. It recorded the details of anyone who had access to the film. It varied the ways and times it delivered reels of the film to cinemas to confuse potential pirates, and even held one or two reels back until the last moment so that cinemas didn't have a complete movie from which copies could be made. In the weeks leading up to the film's release, tech-savvy teams tracked file-sharing sites on the internet for any evidence of pirated copies.

When the film opened in Australia and New Zealand, ushers in every cinema were given night-vision goggles so they could scour the audience for people who might be using camcorders. When the film came to the US two days later, the same tactic caught a member of the audience taping the film at a 9.40am showing in Kansas.

Warner Bros believes the operation was so successful that the first dodgy copy didn't hit the internet until 38 hours after the film's release in Australia. They are convinced this delay was critical in helping the film to its record-breaking $158m first weekend.

"It's so important to try to protect the first weekend because it prevents the pirate supply chain from starting," says Darcy Antonellis, president of Warner's distribution and technical operations. "A day or two becomes really, really significant. You've delayed disc manufacturing. That then delays distribution, which then delays those discs from ending up on street corners for sale."

Not everyone is convinced. On the website techdirt.com, one writer suggested that the millions Warner Bros spent on their anti-piracy efforts were wasted because there was so much excitement about The Dark Knight everyone wanted to see it in cinemas anyway.

"Until the movie industry realizes that it's the experience they're selling, beyond just the content," he said, "it sounds like they're going to be throwing a lot more money down this anti-piracy hole than they're actually 'losing' to piracy." ·