The Sign of Four
By Sir Arthur Conan Doyle
- Release Date: 2025-06-30
- Genre: Mysteries & Thrillers
Description
The Sign of the Four, also called The Sign of Four, is an 1890 detective novel, and it is the second novel featuring Sherlock Holmes by British writer Sir Arthur Conan Doyle. Doyle wrote four novels and 56 short stories featuring the fictional detective.

