Cat in a Ultramarine Scheme is the twenty-second title in Carole Nelson Douglas's sassy Midnight Louie mystery series. Previous titles include Cat in a Topaz Tango, Cat in a Sapphire Slipper, and Cat in a Red Hot Rage. In addition to tales of her favorite feline, Douglas is also the author of the historical suspense series featuring Irene Adler, the only woman ever to have "outwitted" Sherlock Holmes. Douglas resides in Fort Worth, Texas.