In April 1861, Lyndel Keim discovers two runaway slaves in her family's barn. When the men are captured and returned to their plantation, Lyndel and her young Amish beau, Nathaniel King, find themselves at odds with their pacifist Amish colony. As word reaches the Amish settlement that the nation is now involved in a civil war, Nathaniel enlists in what will become the famous Iron Brigade of the Union Army. Lyndel enters the fray as a Brigade nurse, sticking close to Nathaniel as they both witness the horrors of war. Despite the pair's heroic sacrifices, the Amish only see that Lyndel and Nathaniel have become part of the war effort, and both are shunned.