"The Monstrumologist's Assistant" is a novel by Rick Yancey that follows the story of Will Henry, a young orphan who becomes the assistant to Dr. Warthrop, a scientist specializing in the study of monsters. Set in the late 19th century, the narrative explores themes of friendship, fear, and the nature of humanity as Will navigates the challenges of his unusual profession. The story delves into the world of monstrumology, the study of monsters, as Will and Dr. Warthrop confront various creatures and the moral dilemmas that arise from their research. The novel combines elements of horror and adventure, providing readers with a gripping tale of survival and discovery.