When Ruby Murphy—Brooklyn resident, cat whisperer and mad-dash urban bicyclist—notices a human leg in her psychiatrist's fish tank in her third diverting sleuthing adventure (after 2004's Gargantuan
), the limb proves to belong to Tobias Ray, the estranged spouse of Dr. Jody Ray, Ruby's coolly professional therapist. Once over the shock, Jody begs Ruby to help hunt for Tobias, an apparent kidnapping victim. But just when Ruby finds the one-legged Tobias, Jody disappears. Meanwhile, Ruby is inexplicably fired from her job at the Coney Island Museum; her live-in boyfriend suddenly needs "space"; and her only loyal friend is Jack Valentine, her beloved horse. Though the plot meanders and takes a tortoise-and-hare nap occasionally, Estep's wry observations, razor-sharp wit and deliciously vivid characters will keep readers turning the pages. (Sept.)