The adventure starts off as a coming-of-age story for a teenager, Randolph P. McDuff, as he escapes his city life and seeks to start over in the west. On his journey, he meets fellow travelers Romeo Jones, Louis Clark Jefferson, the cranky wagon master Bumpy Snits, his daughter Ornery Sue, and the rootin' tooin' cowgirl Subliminy Jill. This band of misfits headed west meet on a ferry traveling down the Mississippi River, headed by the creepy little Three-Eyed Jack. The ferry crashes, but right before the final plank busts, Jack tells of his hidden gem mine in El Glitterado and presents the travelers with a map. The remaining members band together and travel west, each with a torn piece of the salvaged map. The group eventually joins a wagon train following the Oregon Trail, and even let in two orphans they meet on the way. The rambunctious crew is deemed the ‘party wagon' of the train and is sent to be the last to follow all other wagons. Wacky hijinks ensue, leading to many complications, but throughout the story Randy grows as a character as he logs his daily adventures in a letter he plans to send to his aunt back in Maine. What's made matters worse is that Three-Eyed Jack survived the waterfall and is on the hunt to get his map back.