Chicago is a 2002 musical black comedy crime film based on the 1975 stage musical, which in turn originated in the 1926 play. It explores the themes of celebrity, scandal, and corruption in Chicago during the Jazz Age. The film stars an ensemble cast led by Renée Zellweger, Catherine Zeta-Jones, and Richard Gere. Chicago centers on Roxie Hart (Zellweger) and Velma Kelly (Zeta-Jones), two murderers who find themselves in jail together awaiting trial in 1920s Chicago. Roxie, a housewife, and Velma, a vaudevillian, fight for the fame that will keep them from the gallows. The film marks the feature directorial debut of Rob Marshall, who also choreographed the film, and was adapted by screenwriter Bill Condon, with music by John Kander and lyrics by Fred Ebb.

Chicago received critical acclaim, with particular praise for the performances of the cast. The film went on to win six Academy Awards in 2003, including Best Picture, making it the first musical to win Best Picture since Oliver! in 1968. For her performance, Zeta-Jones won the Academy Award for Best Supporting Actress, the British Academy Film Award for Best Actress in a Supporting Role, and the Critics' Choice Movie Award for Best Supporting Actress. Zellweger won the Golden Globe Award for Best Actress – Motion Picture Comedy or Musical, and Gere won the Golden Globe Award for Best Actor – Motion Picture Musical or Comedy. Chicago was the tenth-highest-grossing film of the year domestically in the United States.

In 1924, housewife Roxie Hart watches vaudeville star Velma Kelly perform ("Overture/All That Jazz") at The Onyx, a Chicago nightclub. Seeking stardom, Roxie begins an affair with furniture salesman Fred Casely, who claims to know the manager. After the show, Velma is arrested for killing her husband and sister upon catching them in bed together. A month later, Casely admits to Roxie that he lied about his connections in order to sleep with her. Enraged, she shoots him dead. She convinces her gullible husband, Amos, to take the fall by telling him she killed a burglar in self-defense. However, when evidence of Roxie's infidelity is uncovered, Amos recants and tells the police that Casely was dead when he arrived home ("Funny Honey"). Roxie is arrested, with District Attorney Martin Harrison declaring she faces execution by hanging.

At Cook County Jail, Roxie is sent to Murderess' Row, supervised by the corrupt Matron "Mama" Morton ("When You're Good to Mama"). She learns the backstories of the other women there, including her idol Velma ("Cell Block Tango"), who rebuffs her attempts at friendship. On Morton's advice, Roxie engages Velma's lawyer, the brilliant Billy Flynn ("All I Care About"). Flynn and Roxie manipulate the press, reinventing Roxie as an originally virtuous Southern woman corrupted by the city's decadent nightlife; she claims that she had the affair with Casely because Amos was always working, but repented and left Casely for Amos, and Casely jealously attacked her ("We Both Reached for the Gun"). The press believe the story; praised by the public as a tragic heroine, Roxie becomes an overnight sensation ("Roxie"). Velma, unhappy at losing the public's attention, tries to convince Roxie to join her act, replacing her murdered sister ("I Can't Do It Alone"), but Roxie, now the more popular of the two rivals, snubs her.

When wealthy heiress Kitty Baxter is arrested for murdering her husband and his two mistresses, the press and Flynn instantly shift their focus to her. To Velma's surprise, Roxie quickly regains the spotlight by claiming pregnancy. Amos is ignored by the press ("Mister Cellophane"), and Flynn, to generate more sympathy for Roxie, convinces him that the child is Casely's, and that he should divorce Roxie in the midst of her predicament. Roxie decides to fire Flynn, believing she can now win on her own. However, when Katalin Helinszki, a Hungarian woman on Murderess' Row (the only inmate who insists on her own innocence), becomes the first woman in Cook County history to be executed by hanging, Roxie realizes the gravity of the situation and rehires Flynn.

Roxie's trial begins, and Flynn turns it into a media spectacle ("Razzle Dazzle") with the help of sensationalist newspaper reporters and radio personality Mary Sunshine. Flynn discredits witnesses, manipulates evidence and even stages a public reconciliation between Amos and Roxie when she claims the child is his. The trial seems to be going well for Roxie until Mama and Velma are listening to the trial and find Roxie's diary, and bring it to court, reading incriminating entries in exchange for amnesty in her own case. Flynn discredits the diary, implying from its legalistic language that it was written by Harrison, who planted it as evidence ("A Tap Dance"). Roxie is acquitted, but her fame is eclipsed moments later when another woman, who had also shot her own husband, shoots her lawyer outside the courthouse. Flynn admits to Roxie that he tampered with her diary himself, in order to incriminate the DA and also free two clients simultaneously. Amos remains loyal and excited to be a father, but Roxie cruelly reveals that she faked her pregnancy.

Roxie continues to pursue a vaudeville career, with limited success ("Nowadays"). The similarly unsuccessful Velma reapproaches Roxie to suggest performing together as a double act consisting of two murderers. Roxie initially refuses, but later accepts when Velma points out that they can perform together despite their mutual resentment. The two stage a spectacular performance ("Nowadays/Hot Honey Rag"), receiving a standing ovation from an enthusiastic audience that includes Flynn, Morton, the jurors, and other acquitted murderesses.

The film is based on the 1975 Broadway musical of the same name, which ran for 936 performances. A film adaptation of Chicago was to have been the next project for Bob Fosse, who had directed and choreographed the original 1975 Broadway production and had won an Oscar for his direction of the film version of Cabaret (1972). Although he died before realizing his version, Fosse's distinctive jazz choreography style is evident throughout the 2002 film, and he is thanked in the credits. The minimalist 1996 revival of the musical proved far more successful, having played more than 10,601 performances (as of December 3, 2023), holding records for longest-running musical revival, longest-running American musical on Broadway and second longest-running show in Broadway history. Its runaway success sparked a greater appreciation of the 1975 original production and renewed stalled interest in a long-anticipated film, which incorporates the influences of both productions.