Everything depends on them....When Georgie Hall decides to walk from Concord, Massachusetts, to Washington, D.C., with a letter to the President and an old flag capable of producing magical visions, no one doubts that she has the will or ability to do it. Along with her stepcousins Eleanor and Eddy, Georgie begins the Children's Crusade to stop the President from building a globally fatal nuclear bomb, known as the Peace Missile. But 450 miles is a long way to walk, and even as the Crusade picks up members along the way, its marchers can't help but wonder if their actions will make a difference, or if it is already too late....