Sam Hummer was a local truck driver from Tucson, Arizona who worked for a Tucson-based produce-shipper called "Red River". His driving partners were Duane Haller and "Pops" Dinwiddie. Eventually Sam's son, Carrol Jo, is old enough to ride with his father and the two of them then become partners as well. Sam changes the lettering on the trailer of his rig to read "Sam Hummer and Son".