Desperate to shield her from scandal, Mary's brother-in-law, Robert Fortune, forces her to accompany him on a mission to China to steal tea plants for the East India Company. But Robert conceals his secret motives - to spy for the British forces, newly victorious in the recent Opium War. His task is both difficult and dangerous - the British are still regarded as enemies and exporting tea bushes carries the death sentence. Thousands of miles from everything familiar, Mary revels in her new freedom and the Chinese way of life - and when danger strikes, finds unexpected reserves of courage.