Despite the density of scholarly engagement with Mozart’s operas, Donna Elvira’s aria ‘Mi tradì quell’alma ingrata’, composed for the 1788 Viennese production of Don Giovanni, has received little sustained, critical attention. Yet this oversight is unjustified, particularly considering the aria’s many stylistic elements that expand beyond the musical language of the original Prague Don Giovanni, and which therefore show Mozart not only deepening Elvira’s characterization but probing new compositional horizons. This article undertakes a thorough, analytic examination of ‘Mi tradì’, focusing especially on its evocation of Elvira’s subjectivity and self-consciousness, and paying particular attention to formal rhetoric and topical reference, both of which, by suggesting affinities with genres such as variation and the free fantasia, move the aria significantly beyond the expressive world often associated with Mozart’s vocal writing. The article closes with brief speculations on the relationship between ‘Mi tradì’ and the composer’s career aspirations in the late 1780s.