This the University of Chicago Press' free book for July.
Title:
The Chinese Maze Murders by Robert Van Gulik
Description: Poisoned plums, a cryptic scroll picture, passionate love letters, and a hidden murderer with a penchant for torturing and killing women lead Judge Dee to the heart of the Governor’s garden maze and the answers to three interwoven mysteries.
The Chinese Maze Murders was the first of van Gulik’s Judge Dee mystery novels.