Antwone Fisher (DEREK LUKE) is a 24-year-old sailor in the U.S. Pacific Fleet who has a problematic attitude that's resulted in various fights, including with fellow sailor Grayson (RAINOLDO GOODING). Accordingly, their commander demotes him and then sends him to see staff psychiatrist Jerome Davenport (DENZEL WASHINGTON) who has just three sessions to figure out what's troubling the young man and make a recommendation about what to do.
At first, Antwone isn't keen on participating and doesn't want to talk about himself or what's eating at him. Yet, Jerome's patience eventually pays off and the sailor begins to open up. He explains that he was born in prison after his father was murdered, and that he and two other boys were raised by Mrs. Tate (NOVELLA NELSON), a script disciplinarian and preacher's wife who didn't like and often beat all of them.
Such beatings and intimidation obviously scarred Antwone as a boy, as did sexual abuse at the hands of an older girl. That's left him unsure of how to act around young women his age, although he does start seeing Cheryl (JOY BRYANT) who works in the Navy base bookstore. He also gets closer to Jerome and his wife Berta (SALLI RICHARDSON), although that begins to make the psychiatrist worry that Antwone is becoming too dependent on him.
Accordingly, he tells Antwone that the only way for him to come to terms with his past is to find his real family and let them know how he feels about them, himself and both the past and present. After some hesitation and more sessions with Jerome that reveal more facts about what shaped him into the man he is today, Antwone and Cheryl then set out to do just that, eventually leading him to meet his mother, Eva (VIOLA DAVIS).