Soling and Chang-wei travel to Japan, in the hope of convincing Japan to aid China in blocking the growing imperialism of Britain, France and America. Along the way, the pair are treated to aspects of samurai culture, as well as the prevalence of karakuri (automata), which were introduced in Jeannie Lin's The Warlord and the Nightingale.
It's nonstop assassination attempts and running across countryside. Also, Soling meets Sagara Satomi, a young woman who crafts elegant guns; the young woman has a very similar experience to Soling's, as Satomi's father was also murdered by his ruler for speaking uncomfortable truths.
The story moves well, and the romance deepens between Soling and Chang-wei, but things are complicated by Chang-wei persistently putting China's political and martial needs before anything else, while tradition keeps Soling from thwacking him upside the head.
Lots of fun, and my fave Yang makes an appearance.