At the beginning of hostilities, Tom Winston, despite the pleadings of his sister, Ellen, who is an ardent Confederate, goes north, and acquires a commission in the Federal army. Frank Carey has entered the Confederate service, though his sister, Ethel, furiously denounces him as a traitor, and asserts her intention of herself serving the Union. Both girls become identified with the secret service department of the South and North, respectively. Tom is with Grant, and Frank with Johnston, and the movements of the armies bring them into the neighborhood of their homes. Tom has with him Don, a dog, which had been used in the old days to carry messages between his master and Ethel. Union headquarters are established in the Winston home, affording Ellen an opportunity to acquire many valuable secrets which she communicates to Frank, and it is the belief that some officer is proving a traitor.
