Twelve-year-old Elias is sent from his Virginia home to Dr. Crogan’s experimental hospital located within the Mammoth Caves of Kentucky, in the hopes that he can be cured of consumption (tuberculosis). In this pre-Civil War setting, patients are served by slaves, who also lead cave tours. When Elias surreptitiously follows a slave named Stephen into a tunnel, he discovers a network of secret tunnels that house a hidden community of runaway slaves. When a patient and former boat crew member, Pennyrile, gets suspicious and begins investigating, the runaway slaves must quickly hide their existence. The slaves forced to work at the Mammoth Cave protect their pride and dignity in multifaceted manners. Stephen and another slave named Jonah play jokes on the white tourists, such as making them believe that they have encountered a ghost. Descriptions of Dr. Croghan’s primitive medical treatments, such as intentional bleeding, forced vomiting, and homemade instruments, illustrate the painful and fruitless state of health care for tuberculosis patients at that time. A further reading section describes the author’s personal connection to the story, provides additional titles, and includes details about the real-life characters in the story and the treatment of tuberculosis. This work boasts richly developed African American characters and extraordinary settings. VERDICT Recommended for libraries wanting to expand their historical fiction collection.–Jennifer Schultz, Fauquier County Public Library, Warrenton, VA