Irene At Large by Carole Nelson Douglas

A fiercely independent adventuress-turned-soprano and her prim, resourceful companion are drawn into a labyrinth of Continental intrigue after a tantalizing warning and a brazen theft set dangerous forces in motion. Crossing from glittering salons to shadowed backstreets, they confront a ruthless adversary whose schemes entangle royalty, spies, and the theater world, forcing them to rely on clever disguises, quick wit, and daring gambits. As loyalties are tested and past secrets resurface, a high-stakes showdown puts hearts and reputations on the line—and proves that underestimating this sleuth is a deadly mistake.