World War I is raging and British officer Michael Andrews (Cary Grant) is fighting on the eastern front. After being captured by a group of Kurds, Andrews is saved by a British agent named John Stevenson (Claude Rains), and the two form an odd friendship. Andrews then injures his leg during a dangerous mission and winds up in a Cairo hospital. There he falls in love with a nurse (Gertrude Michael), who reveals that she is married. Her husband, in fact, is John Stevenson.