On a cold October day a leaky yacht sailed into an unknown bay. It was 1661, and the two low-level Dutch bureaucrats who rowed ashore thought they'd return to their ship the same night. Instead they were swept up on a weeks-long journey into China, until finally they found themselves bowing before one of the most powerful men in the imperium: the Jingnan Prince Geng Jimao. Their clothes were tattered, they had no gifts to give, their translator was incompetent, and they were hopelessly out of their league, yet their audience with Geng led to one of the most unlikely alliances in world history, between the Calvinist merchants of the Dutch East India Company and the Buddhist Qing Dynasty, which was struggling to extend its rule over all of China.