What would you do if you were accused of a murder, you had not committed... yet?
In Washington, D.C. in the year 2054, John Anderton and his team of Precrime police officers are in the midst of apprehending a suspect who is about to commit a murder. They are acting on data obtained from the "precogs," three mutated humans who can see into the future. Only the names of the victim and perpetrator, and the time and date of the crime, are explicitly given; all other facts must be determined by studying the precogs' visions, which are transmitted from their brains directly into the Precrime computer system.
As Anderton works, he is observed by Danny Witwer, an agent from the United States Department of Justice. Witwer has been sent to evaluate the system because the country is about to vote on whether to expand the Precrime program nationally. After the suspect has been apprehended, the murder reappears on the displays. It is explained that the precogs sometimes think about a crime that has been stopped, and that these “echo” images are deleted from the system. That night, as on most nights, Anderton buys street drugs (to which he is addicted) and reminisces over home movies of his ex-wife Lara and the couple's missing six-year-old son.
The next morning, he and Witwer tour the chamber in which the precogs are kept semiconscious and wired up to the system. After Witwer has gone, the precog Agatha snaps fully awake, and images of a woman being murdered play across the chamber’s video screens. When Anderton investigates, he finds that the visions from the other two precogs, Arthur and Dashiell, are on record, but Agatha’s is not.