The struggling Shady Rest Hotel, run by friendly and kind-hearted Kate Bradley, her big thinking but slow moving Uncle Joe Carson, and her three pretty daughters - boy crazy Billie Jo, bookish but romantic Bobbie Jo and tomboy Betty Jo - is located along a spur line of the C & FW Railroad which connects the towns of Hooterville and Pixley. The relic but beloved train called the Cannonball operates this route. Charley Pratt and Floyd Smoot, the engineer and conductor of the Cannonball, believe those at C & FW headquarters have forgotten all about them, especially as this spur line doesn't even connect to the main line. Charley and Floyd are correct as corporate bigwigs see the spur line on a system-wide map and initially believe it is just an ink smudge. They send one of their own, Homer Bedloe, to Hooterville Valley to investigate. The ruthless Bedloe sees that the Cannonball runs almost at the bequest of the residents instead of to strict regulations on fixed schedules and fixed stops. As such, he vows to shut the Cannonball down, which would not only mean that Charley and Floyd would lose their jobs, but that the Shady Rest would go out of business, as the train is the sole means of transportation to and from.
—Huggo