With dashing Scotland Yard Inspector Alec Fletcher at her side, Daisy is enjoying a delightful performance of Verdi's Requiem, featuring her neighbor Muriel Westlea's celebrated sister, Bettina. But when all that emerges from the doomed diva's vocal chords is a dying gasp, Daisy soon discovers that the notoriously difficult opera star had her share of adversaries... Did someone fatally poison the acclaimed mezzo? Will Daisy's investigation end on as bitter a note as Bettina's fateful last performance?