The narrator of "Sonny's Blues" sees himself as a responsible family man who has used his intelligence and hard work to escape from his background. His brother, Sonny, is the opposite, a failure who was sucked into Harlem's underworld and ends up in prison.

What the responsible brother never realized is that Sonny was just as desperate to escape from Harlem and the drug culture as he was himself and that he used music as a means of escape. The narrator believes that drugs are part of the lifestyle of a musician and that the two always go together. Sonny shows him that when he pours his soul into music, he does not need drugs: in his life, the two are alternatives. Meanwhile, staying in school as his brother wanted him to do was exposing Sonny to the dangerous drugs culture of the area. He ran away from drugs, not from respectability and education.

The narrator is a teacher by profession, but the final scene of the story shows him in the position of a student, in the audience, while Sonny teaches him about their lives and life in general by the way in which he plays the blues on stage. This final role reversal, the culmination and resolution of a series of misunderstandings between the brothers, is the primary situational irony in the story.