Hollywood film studios are launching a campaign to stop people who download movies illegally from the internet.
They claim web piracy costs them more than £1.5bn a year, and want to sue anyone in the US involved in the trade.
Dan Glickman, head of a group which represents seven studios, said the pirates would be caught: "We know who they are and we will go after them."
The film studios are following similar moves by the music industry which has also targeted the pirates.
The US government says fake goods, including films and music, cost the US $250bn a year.