In New Orleans, a shooting takes place at a stock brokerage firm. Among the dead is Jacob Wood. The shooter was a failed day trader who apparently killed eleven people and wounded several others in the event. Two years later, with attorney Wendell Rohr, Jacob's widow Celeste takes Vicksburg Firearms to court on the grounds that the company's gross negligence led to her husband's death. During jury selection, jury consultant Rankin Fitch and his team communicate background information on each of the jurors through electronic surveillance to defense attorney Durwood Cable, who is in the courtroom.
In the jury pool, Nicholas (Nick) Easter pretends to try to get himself excused from jury duty. Judge Frederick Harkin decides to give him a lesson in civic duty, and Fitch tells Cable that the judge has now given them no choice and that he must select Nick as a juror. Nick's congenial manner wins him acceptance from his fellow jurors, but Frank Herrera, a Marine veteran, takes an instant dislike to him.
A woman named Marlee makes an offer to Fitch and Rohr by phone: she will deliver the desired verdict to the first bidder. Rohr dismisses the offer, assuming it to be a tactic by Fitch to obtain a mistrial. Fitch asks for proof that she can deliver, though, which Nick provides by getting a juror expelled. By observing the jurors' behaviour through concealed cameras, Fitch identifies Nick as the influencer and orders his apartment to be searched, but finds nothing. Marlee retaliates by getting one of Fitch's jurors bounced. Fitch then goes after three jurors with blackmail, leading one, Rikki Coleman, to attempt suicide. He also sends his men to find a concealed device in Nick's flat on which key information has been stored, after which they leave and set fire to the apartment. Nick shows the judge video footage of his apartment being searched the first time, and the judge orders the jury sequestered.
Rohr's key witness, a former Vicksburg employee, doesn't show up. After confronting Fitch, Rohr decides that he cannot win the case. He asks his firm's partners for $10 million to pay Marlee. Fitch sends an operative, Janovich, to kidnap Marlee, but she fights him off and raises the price to $15 million. On principle, Rohr changes his mind and refuses to pay. After the CEO of Vicksburg Firearms loses his temper under cross-examination as a witness and makes a bad impression on the jury, Fitch agrees to pay Marlee to be certain of the verdict.
Fitch's subordinate Doyle, who is investigating Nick, finds that Nick is, in fact, Jeff Kerr, a law school drop-out. He then travels to Gardner, Indiana, where Jeff and his law school girlfriend Gabby (ie. Marlee) both come from. Doyle gently quizzes Gabby's mother who tells him that Gabby's sister died in a shooting years ago when she was in high school. At the time, the town had sued the gun manufacturer and lost; Fitch had helped the defense win the case. Doyle concludes that Nick and Marlee's offer is a set-up, and he calls Fitch, but it is too late as the money has already been paid.
Nick receives confirmation of receipt of payment, and he makes a speech, asking them to review the facts, and says that they owe it to Celeste Wood to deliberate, much to the chagrin of Herrera, who launches into a rant against the plaintiff, which undermines his support. The gun manufacturer is found liable, with the jury awarding $110 million in general damages to Celeste Wood.
After the trial, Nick and Marlee confront Fitch with a receipt for the $15 million bribe which they will make public unless he retires. Fitch asks how they got the jury to vote for the plaintiff, to which Nick replies that he didn't; he just stopped Fitch from stealing the trial by getting the jury to vote with their hearts. They inform him that the $15 million will benefit the shooting victims in Gardner.
John Cusack as Nicholas "Nick" Easter
Gene Hackman as Rankin Fitch
Dustin Hoffman as Wendell Rohr
Rachel Weisz as Marlee
Bruce Davison as Durwood Cable
Bruce McGill as Judge Frederick Harkin
Jeremy Piven as Lawrence Greene
Nick Searcy as Doyle
Stanley Anderson as Henry Jankle
Marguerite Moreau as Amanda Monroe
Leland Orser as Lamb
Gerry Bamman as Herman Grimes
Nestor Serrano as Janovich
Joanna Going as Celeste Wood
Cliff Curtis as Frank Herrera
Jennifer Beals as Vanessa Lembeck
Bill Nunn as Lonnie Shaver
Juanita Jennings as Loreen Duke
Nora Dunn as Stella Hulic
Guy Torry as Eddie Weese
Rusty Schwimmer as Millie Dupree
Rhoda Griffis as Rikki Coleman
Corri English as Lydia Deets
Lori Heuring as Maxine
Dylan McDermott (uncredited) as Jacob Wood
An adaptation of John Grisham's 1996 novel The Runaway Jury