When sixteen-year-old AJ Flynn finds a mysterious key at his new job at a London law firm, he and his scrappy friends begin a series of journeys to 1830 where they discover a crime only they can solve.
- ISBN: 9780399549977
- Author: Gardner, Sally
- Published: 2016 , Delacorte
- Themes: London, Mystery and detective stories, Time travel
- Descriptors: England (UK), Fiction, Intermediate (ages 9-14)
- No. of pages: 228