The bloody Civil War has ended at last, and Marshal Ridge Parkman is looking forward to visiting his family at last in exhausted, war-torn western Missouri. But no sooner has he settled in to relax and catch up on things, than whimsical fate drops a mission in front of him that he can hardly ignore. The next thing he knows, he's on a steamboat heading down the Missouri and Mississippi Rivers. His assignment is to track a father-son team who are...