Shortly following the premiere of Lucia di Lammermoor in 1835, performances of this opera often featured a strange substitution: sopranos performed the rondò-finale from one of Donizetti's earlier operas, Fausta, in place of the now-famous mad scene aria. At least four productions were affected and this alteration was performed by some of the most famous sopranos of the time. This article explores the brief tradition of altering the mad scene by looking carefully at its origin and subsequent appearances, discussing its effects on the experience of hearing Lucia di Lammermoor as a whole, and investigating the possible reasons why this substitution lasted only for a brief period of time.