Driven to Suicide: Rather than be arrested, Rosa takes a dose of the same cyanide used to kill Elvira, and perishes after performing the finale.
Murder the Hypotenuse: Rosa poisoned Elvira when she discovered the younger woman was having an affair with her lover, Carlo. By the time Carlo assures Rosa of his love, it's too late.
Stalker with a Crush: Mr. Peters, the stagehand, is obsessed with Rosa, sending her bouquets and writing her suggestive letters, but he is not the killer.
