Femme Fatale by Carole Nelson Douglas

Irene Adler and her steadfast chronicler, Nell Huxleigh, answer a desperate appeal from a dangerously alluring woman, drawing them into a web of blackmail, murder, and press-fueled scandal that spans the glittering demimonde and the Gilded Age power structure; as Pinkertons, newspapermen, and powerful men close in, the pair chase elusive truths that entangle with Irene’s own shadowed origins and force perilous choices about love and loyalty.

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