Andrew Beckett, portrayed by Tom Hanks, is a senior associate at Philadelphia's largest law firm, but he harbors a significant secret: he is gay and suffering from AIDS. While living with his partner Miguel Álvarez (Antonio Banderas), Beckett keeps his sexual orientation hidden from his colleagues. On the day he receives the firm's most crucial case, a partner notices a small lesion on his forehead, prompting Beckett to take time off to conceal his condition.
During this period, he meticulously completes the necessary paperwork for the case and instructs his assistants to file it the next day, the very last moment before the statute of limitations expires. Unfortunately, Beckett suffers severe bowel spasms and is rushed to the emergency room. From his hospital bed, he receives frantic calls from the firm about the missing complaint, which is eventually located just in time for filing. However, the following day, Beckett is unceremoniously dismissed by the partners who had previously called him their "buddy." They now question his competency based on the missing document.
Believing his termination is linked to his AIDS diagnosis, Beckett seeks legal representation and approaches personal injury lawyer Joe Miller, with whom he has a past connection. Initially, Miller is reluctant to take on Beckett's case because of his own homophobic views and lack of knowledge about AIDS. After consulting his doctor about the risks of contracting the virus, he decides against representing Beckett. With no other lawyers willing to help him, Beckett takes up his defense.
While at a law library, Miller witnesses the prejudice Beckett faces as patrons move away from him. Witnessing this treatment ignites a shift in Miller's perspective; he chooses to represent Beckett. As the trial unfolds, the head of the firm, Charles Wheeler (Jason Robards), takes the stand, painting Beckett as incompetent and suggesting that he caused his illness through reckless behavior. However, during the trial, Miller successfully reveals that Beckett's condition was visible due to the lesions and that homophobic attitudes were prevalent in their workplace.
As the court proceedings continue, Beckett admits to engaging in anonymous encounters with men but gains sympathy when a partner reveals he suspected Beckett's illness but chose to remain silent. Tragically, Beckett collapses during a critical moment of the trial, leading to a jury decision in his favor, awarding him a staggering $4.5 million in damages.
In a poignant scene, after the verdict, Miller finally finds the courage to show affection towards Beckett in the hospital. Following Beckett's passing, the film concludes with a moving reception held in his honor, where guests, including the Millers, reflect on Beckett's life through home movies, mourning the loss of a vibrant spirit.
