| Spoiler warning: The following contains plot details about|
the entire movie.
As the film opens, legislation is pending to expand surveillance powers of law enforcement agencies. Republican Congressman Phil Hammersleigh (Jason Robards, uncredited), who is trying to stop the bill because he believes it's an invasion of privacy, is killed by several rogue NSA agents loyal to Thomas Reynolds (Jon Voight), an official trying to push the bill to secure a promotion for himself within the agency. The agents then plant a bottle of heart medication at the scene to make it look as though Senator Hammersleigh died from a heart attack. They are not aware that the murder is being recorded by a video camera aimed directly across the lake used to track migratory patterns of Canada Geese.
A researcher named Daniel Zavitz (Jason Lee) removes the tape from the camera and, upon playing it, sees that Senator Hammersleigh was murdered and did not die of a sudden heart attack as was reported on the news. However, an NSA agent saw Zavitz retrieve the tape from its camera. Zavitz copies the tape onto a computer cartridge. When the agents show up, he hides it in a TurboExpress and runs.
Robert Clayton Dean (Will Smith) is a labour lawyer working in trade union cases. While shopping at a lingerie store for his wife, Dean encounters Zavitz, an old friend from Georgetown University, fleeing the NSA agents. Zavitz drops the cartridge with the murder footage into Dean's shopping bag and flees. Outside the store, Zavitz takes a bike, rides across a busy street, and is hit by a firetruck and killed. Using high-tech satellite technology, the agents quickly determine that Dean likely has the tape, and they endeavour to get it back. The agents visit Dean, who is unaware that Zavitz gave him the video, and attempt to get him to turn it over. When he does not cooperate, they disrupt his credit line and invade his personal life. They ransack and bug his house and install tracking devices in his watch, cellular phone, and clothing. When some time passes and he still does not come around, they turn up the pressure by killing Dean's ex-girlfriend and associate Rachel (Lisa Bonet) and framing him for the murder.
Prior to her murder, Rachel had helped Dean with difficult investigations relating to his law practice. She had an associate, Brill (Gene Hackman) who could conduct difficult electronic surveillances with a minimum of trouble. After Rachel is killed, Brill and Dean make contact and wind up working together to combat the rogue agents. Among one of their exploits, Brill manages to turn the tables on Reynolds' by ruining his credit, planting surveillance equipment in his home and even sending flowers as an indication he might be having an affair, which raises his wife's ire. After the video of Hammersleigh's murder is accidentally destroyed, Dean and Brill stage an encounter with the agents. After their initial plan goes wrong, Dean claims that the leader of the Pintero mafia family has the tape Reynolds is after. When they go to retrieve it, the situation becomes a Mexican standoff between the agents and mobsters. The mafia headquarters, which is under FBI surveillance, proves an untenable location for the conspiracy to remain a secret. A large shootout ensues, with Dean and Brill among the survivors; Reynolds and nearly all of the agents involved in the conspiracy and most of the mobsters are killed. The FBI sweeps in, the plot behind the legislation is revealed, and the only two surviving conspirators, computer nerds Fiedler (Jack Black) and Jamie (Jamie Kennedy) are under investigation by law enforcement.
Dean is cleared of all charges and returns home with his wife. Brill, who quietly left the scene of the bloodbath after he saw that Dean survived, resurfaces with a message to Dean through the television in his home. First, Dean sees a live image of himself on the screen and fears that his troubles have returned, only to then see a blurred image on screen revealing Brill's cat and a tropical scene of Brill's legs with a message reading, "Wish you were here."
- Will Smith - Robert Clayton Dean
- Gene Hackman - Edward 'Brill' Lyle
- Barry Pepper - Det. David Pratt
- Jon Voight - Thomas Brian Reynolds
- Regina King - Carla Dean
- Ian Hart - Det. John Bingham
- Lisa Bonet - Rachel F. Banks
- Jake Busey - Krug
- Scott Caan - Jones
- Jamie Kennedy - Jamie Williams
- Jason Lee - Daniel Leon Zavitz
- Gabriel Byrne - Fake Brill
- Stuart Wilson - Congressman Sam Albert
- Jack Black - Fiedler
- Laura Cayouette - Christa Hawkins
- Loren Dean - Loren Hicks
- Dan Butler - NSA Director Shaffer
- Seth Green (uncredited) - Computer Tech
- Tom Sizemore (uncredited) - Pintero
- Philip Stamper (uncredited) - Extra
- While most of the addresses and locations mentioned in the film are in Washington, D.C., the vast majority of the filming was done in the neighbouring city of Baltimore, Maryland.
- The film's setting is around Christmas time, but was actually filmed in January and February 1997. Many of the filming locations were asked to haul all of their holiday décor back out and "re-decorate."
- Filming crews had hoped to film a few "white Christmas" scenes, but the winter of 1997 brought warm temperatures, and no snow, to the Baltimore area.
- The film had a Technical Surveillance Counter-Measures (TSCM) consultant in the staff, who also played a minor role as a spy shop merchant.
- The film deals heavily with issues that were subsequently debated on the United States Patriot Act.
- Reynolds, the antagonist and foremost proponent of the anti-privacy bill, was born on September 11, 1940 which was the date Bell Labs researcher, George Stibitz, demonstrated the first remote operation (i.e. over a phone line) of a computer machine.
- Mel Gibson and Tom Cruise were considered for the part that went to Will Smith. George Clooney was also considered for a role in the film, which may have been that of Reynolds.
- In the film, the ferry that Dean rides is mentioned to have a destination to Gibson Island, a real island on the coast of the Chesapeake Bay. However, no such ferry exists, as Gibson Island is a privately owned corporation.
- Shots of the NSA satellite, seen frequently during the movie, were re-used in the pilot episode of the TV series 24.
- Nineteen Eighty-Four (1984)
- The Conversation, Gene Hackman's 1974 film, is referenced several times in "Enemy of the State." For the old identification photo appearing in Brill's dossier, a photo of Hackman as surveillance expert Harry Caul in "The Conversation" is shown. Brill's security center in an abandoned warehouse is very similar to that used by Harry Caul during the events of "The Conversation". Also, at Brill's warehouse, Barry Pepper (playing one of Reynold's agents) is wearing the same type of plastic raincoat that Hackman's character wore in "The Conversation." Some fans have speculated that Brill is, in fact, an older and wiser Caul.