Jennings (The Major's Daughter) introduces readers to the rough and tumble town of Joplin, Mo., in this fun inspirational adventure set in 1898. Undercover Pinkerton agent Calista York is hired to find Lila, the daughter of a Chicago gangster with connections to Calista's boss. Lila was last seen being held in a brothel in Joplin, and though Calista's wary of the assignment because she has relatives in the area who may blow her cover, she takes the job, convinced that "God had called her on this path" to rescue Lila before she is harmed. Matthew Cook, a new pastor in Joplin, is eager to save souls in the derelict town. After spotting Calista at a brothel and then at a whiskey shop, Matthew determines to protect her and help her reform her life. Calista's work in Joplin becomes a complicated balancing act as she deals with meddlesome family, her deepening feelings for Matthew, her investigation and the corrupt local police, and a looming deadline to find Lila. Just when Calista is recalled by her boss and gives up searching for Lila, Matthew discovers the truth about Lila's whereabouts and races to find Calista before she reports back. Jennings nicely lays out the competing interests and introduces Joplin locals, such as orphanage director Mrs. Fairfield, who promise good things for future entries in the series. Full of colorful characters and unexpected twists, Jennings's entertaining story is her best yet. (Dec.)