Paranormal Activity is a 2007 American supernatural horror film written and directed by Oren Peli. The film centers on a young couple, Katie and Micah, who are haunted by a supernatural presence in their home. It is presented in the style of "found footage", from cameras set up by the couple in an attempt to document what is haunting them.
Originally developed as an independent feature and given film festival screenings in 2007, the film was acquired by Paramount Pictures and modified, particularly with a new ending. It was given a limited U.S. release on September 25, 2009, and then a nationwide release on October 16, 2009. The film earned nearly $108 million at the U.S. box office and $194 million worldwide. Paramount/DreamWorks acquired the U.S. rights for $350,000. It is the most profitable film ever made, based on return on investment, although such figures are difficult to verify independently as this is likely to exclude marketing costs.