With dashing Scotland Yard Inspector Alec Fletcher at her side, Daisy Dalrymple 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, among them a smugly philandering tenor, a burly Russian bass, and even her own vocal coach husband, with whom she shared a hardly harmonious marriage. Did one of them fatally poison the acclaimed mezzo? Or was it someone else - someone determined to see that Daisy's investigation ends on as bitter a note as Bettina's fateful last performance...