McKay, a professional freelance itinerant trucker who travels the country's highways in a red and white Kenworth K-100 Aerodyne (a COE semi truck) with his pet chimpanzee Bear, named after Bear Bryant, the famed football coach for the University of Alabama.

A frequent guest star in the first season is Sheriff Elroy P. Lobo (Claude Akins,[3] who previously starred in the trucking series Movin' On), whose character eventually spun off onto his own show The Misadventures of Sheriff Lobo along with guest character "Waverly" Ben Cooper.

Two episodes in season two, "Eyes of Texas" (1979) and "The Girls on the Hollywood High" (1980), were designed as prospective pilots for a series about a pair of private detectives called Heather Fern (Rebecca Reynolds) and Caroline Capodi (Lorrie Mahaffey in the first one, Heather Thomas in the second).

His nemesis is Rutherford T. Grant (Murray Hamilton), the corrupt head of the state's Special Crimes Action Team, who is a secret partner in a competing trucking company.

is unable to hire experienced truckers, and is forced to hire seven beautiful young female truckers, consisting of Grant's daughter Cindy (Sherilyn Wolter), twins Teri and Geri (Candi and Randi Brough), no-nonsense Angie (Sheila Wills), Samantha (Amanda Horan Kennedy), Callie (Linda McCullough), and a busty blonde nicknamed "Stacks" (Judy Landers), along with a female dispatcher, Stacy (Susan Woollen).