It's 1925 China and Walter (EDWARD NORTON) and Kitty Fane (NAOMI WATTS) have arrived in a remote village afflicted with cholera. He's a bacteriologist who wants to find a treatment and/or cure for the disease, while she's a socialite who married him only to avoid becoming a future spinster. Neither is happy in their relationship since she recently had an affair with Charlie Townsend (LIEV SCHREIBER), the English Vice Consul.
As her punishment, Walter has forced her to accompany him to his latest post where she finds herself amongst disease-ridden villagers, with nothing to do, and British Deputy Commissioner Waddington (TOBY JONES) as their only neighbor. With tension between the Chinese and British being quite high, the situation is volatile for the foreigners, with military officer General Yu (ANTHONY WONG) assigning a bodyguard for Kitty just in case things should come to a head.
Her interest, however, eventually turns to the local orphanage and the nun who runs it, the Mother Superior (DIANA RIGG). As she becomes involved with the kids there, Kitty begins to realize the error of her self-absorbed ways, as well as the importance of what Walter is trying to do. From that point on, she experiences a rebirth amongst all of the death around her.