Music and especially opera are a large and virtually unworked theme in Nabokov's oeuvre. Allusions to opera figure in almost all of his works of the European period, although they diminish in the American period. On the motif level they resonate with the major themes of N.'s work symptomatically marking their development from "Orpheus" to "Faust." Enhancing the parodic function, the opera allusions become structurally complex. They acquire the function of a substitute addressee, an internal roster of parallel referential texts, diversify their own variability, and increase unpredictability. In doing so, they become what we might call Nabokov's opera phantoms.