The book is categorized as young adult (YA) fiction, specifically a mystery/detective story.
Page counts vary across editions (listed values include about 400 and 416 pages). The suggested age range is 13–19 years.
The book is set in the same mystery continuity and follows the same teen sleuth investigating a case outside her usual setting; it functions as a stand-alone continuation tied to earlier events.
The narrative alternates between the present and past events—most notably incidents in 1978—revealing the cold-case history alongside the current investigation.
The main character is portrayed as smart and resourceful when solving puzzles; her lifelong anxiety is shown as an important part of her character and influences how she approaches investigations.
