Jude Whetstone and Lyyndaya Kurtz, whose families are converts to the Amish faith, are slowly falling in love. Jude has also fallen in love with flying that new-fangled invention, the aeroplane.The Amish communities have rejected the telephone and have forbidden motorcar ownership but not yet electricity or aeroplanes.
Though exempt from military service on religious grounds, Jude is manipulated by unscrupulous army officers into enlisting in order to protect several Amish men. No one in the community understands Jude's sudden enlistment and so he is shunned. Lyyndaya's despair deepens at the reports that Jude has been shot down in France. In her grief, she turns to nursing Spanish flu victims in Philadelphia. After many months of caring for stricken soldiers, Lyyndaya is stunned when an emaciated Jude turns up in her ward.