Christopher Tietjens is a brilliant government statistician serving in the British Army in France and Belgium during World War I. Over the course of his service, Tietjens, who languishes in a soul-draining marriage to a willful socialite wife, meets and falls in love with a spirited young suffragette named Valentine. But their affair is doomed from the start, beset on all sides by the perils of warfare and Tietjen's vindictive wife's unrelenting campaign to demoralize him.