Sel and Hol Danner, identical twin brothers who can exchange thoughts without actually speaking, grow up together in Frederick, Maryland. When the American Civil War breaks out, they separate for the first time in their lives. Sel fights for the North because he hates slavery. Hol fights for the South because it's "home." Cora Dee Soyer, who loves them both, can't pray for either side because that would be praying against one of the boys. The boys discover they can no longer think to each other until the two sides meet at the Battle of the Monocacy at their home town. Brother against brother is real and reflects actual history. The changes in their lives reflect the massive transformation in all lives during this period of American history. It's as though the world is turned upside down with things never being as they were.