Forget Texas. In Somerset Maugham's classic The Painted Veil, everything's bigger in China -- both the external and internal landscapes seem to stretch far outside what is natural, or bearable -- and director John Curran has been inspired, in an epic way, to capture those extremes in his adaptation. It's a romance in the grand tradition, set in the ever-serviceable 1920s, and features a union of convenience, Naomi Watts in a marcelled bob, Ed Norton in a series of white linen suits, some sloppy adultery, a ghastly act of revenge, China, and that old romantic stalwart, the cholera. The Painted Veil is also a sophisticated portrait of a marriage: two people struggling to figure out how such misshapen, chewed-up pieces could possibly be expected to fit together. The cultural gulf that the English couple feels once they are stuck deep in rural China, a colonial shambles on the brink of an uprising, mirrors their personal disconnect even as it forges a bond between them.

Ed Norton plays Dr. Walter Fane, a self-serious, socially stunted bacteriologist who falls in love with Kitty (Naomi Watts), a veteran socialite whose sell-by date is rapidly approaching, the moment he sees her. Kitty accepts Walter's knee-jerk marriage proposal mainly because it is a ticket out of her parents’ house -- and England -- as Walter has taken a position in Shanghai. Despite his dedication to her, eventually Kitty has to face it: Walter is a drip and a square, and no sooner is she introduced into British colonial society than she is swapping knickers with an English Vice Consul, played with sonorous élan by Liev Schreiber.

Chris Rock likes to say if you've never wanted to kill your partner, you've never been in love; he and Walter may have found some unlikely common ground. When Walter discovers the affair, he coolly announces that he has volunteered for service in a remote, cholera-stricken region of China, and if Kitty doesn't accompany him he’ll divorce her, quite publicly, for adultery. Ever fair, he gives Kitty the opportunity to discuss her options with her married lover, and when Watts’s face shatters as she is confronted with Shreiber's cowardice, it is the purity of her devastation, not her naiveté, that resonates.

The couple are carried through the Chinese countryside like contaminants, held high above the heads of their guides, and upon arrival at their destination they set their jaws and their narrow English hips and square off for a long, private match at the passive-aggressive Olympics. Norton, with his pencil neck and high, squeaky punk voice, uses his innate ability to channel both vulnerability and viciousness to almost unbelievable effect; the truly marvelous transformation, however, is watching him tap into a Gary Cooper-ish, somber string bean appeal as Walter and Kitty slowly drop their defenses and realize they might be all they have.

Refusing each other with a donkey-headed tenacity that rivals that of the Chinese villagers who insist on burying the cholera's victims by the water (even though it is contaminating their water supply and killing them in turn), Walter and Kitty trade barbs on their impending deaths with a breathtaking chill. Walter, who has never actually practiced medicine, has to face the fact that his white-hot plan might not have been his best work, and together the couple struggle to help the villagers, if not do them harm, or have harm done. Finding enough grace within yourself to spare some for others is the task of any relationship -- perhaps our task as humans -- and in The Painted Veil, both marriage and service to those in need are tenable only when love and duty become one.