Adam Johnson is a talented African-American jazz cornetist whose life is shadowed by ill health, racism, alcoholism, and a short temper, as well as guilt over the deaths years before of his wife and child. His best friend Nelson Davis and Vincent, a younger White trumpeter whom he mentors, care about him.
One night, he arrives at his New York home drunk after leaving his jazz quintet and finds civil-rights activist Claudia Ferguson and her grandfather Willie Ferguson, a famed jazz trumpeter, waiting in his apartment. Adam is rude to them and makes a vulgar pass at Claudia.
The next day, sober and remorseful, he apologizes and starts to form a wary friendship with Claudia and Willie. Soon he becomes romantically involved with Claudia, though Nelson warns that Adam risks hurting her. Claudia, determined not to let him destroy himself, tries to help him reform.
That relationship brings a measure of stability, and Adam begins to change for the better—though his temper remains a constant threat, and he finds himself clashing with police and ending up under arrest. Claudia is upset by his willingness to provoke authorities, while Adam cannot fathom why he should submit to humiliation.
Booking agent Manny wants to send Adam on a tour of the South, but warns of possible adverse treatment there. Adam's anger flares again when he violently lashes out at a jealous former girlfriend who had just slapped Claudia.
Despite the turmoil, Claudia moves into his apartment to support him, and the two renew their bond. She helps him confront the truth of the accident that killed his family, admitting that his guilt and self-destructive behavior were partly connected to that night.
Adam agrees to reunite with his old group, but the club owner faces pressure from the venue to ban him. The conflict pushes him toward a breaking point.
Manny sends him on the South tour; during a performance, an awkward moment when he embraces Vincent triggers a hostile reaction from the audience. The tour goes on, but the strain continues to mount as Adam fights to control himself. When they return home, he proposes marriage to Claudia.
Backstage, Vincent is attacked in front of Claudia and Adam, who remain frozen as the assault unfolds. Claudia later reflects that she changed Adam and, in her view, stripped him of his former manhood. Adam reappears onstage but is weakened and pained, delivering a brilliant yet feverish trumpet performance before collapsing and dying.
