**Penny Nichols and the Mystery of the Lost Key by Joan Clark. Price: Free. Genre: Historical, Historical Fiction, Classics. Rated: 4.4 stars on 47 Reviews. 135 pages. ASIN: B01C0T6I9K.
The Red Triangle by Arthur Morrison. Price: Free. Genre: Historical Mystery, Suspense. Rated: 4.8 stars on 4 Reviews. 304 pages. ASIN: B01BZE7LG0.