Elsie Mae has long treasured summers with her grandparents in the Okefenokee Swamp, so she is devastated to hear that a shipping company plans to build a canal right through it. What will that mean for the people and animals that call the swamp home? So she writes a letter directly to President Franklin Roosevelt himself and sets off to enjoy what may be her last happy summer there with her new dog, Huck. But when she arrives, she discovers a team of hog bandits who have been stealing from the swamper families. When her cousin Henry James, who dreams of one day becoming a traveling preacher like his daddy, shows up, Elsie doesn't think things could get worse. But then she devises a plan to use Henry and his "Hallelujahs" to help stop the thieves-and maybe make just enough noise to gain Roosevelt's attention...