Two unlikely allies race through the cobbled streets of 1920s London in search of a killer targeting Chinese immigrants. London, 1924. When shy academic Lao She meets larger-than-life Judge Dee Ren Jie, his life abruptly turns from books and lectures to daring chases and narrow escapes. Dee has come to London to investigate the murder of a man he'd known during World War I when serving with the Chinese Labour Corps. No sooner has Dee interviewed the grieving widow than another dead body turns up. Then another. All stabbed to death with a butterfly sword. Will Dee and Lao be able to connect the threads of the murders-or are they next in line as victims? John Shen Yen Nee and SJ Rozan's groundbreaking collaboration blends traditional gong'an crime fiction and the most iconic aspects of the Sherlock Holmes canon. Dee and Lao encounter the aristocracy and the street-child telegraph, churchmen and thieves in this clever, cinematic mystery that's as thrilling and visual as an action film, as imaginative and transporting as a timeless classic.