Riley's career was stagnant until former Mercury Records producer Shelby Singleton received a demo tape of Riley's voice. Singleton was starting and succeeding with his own label, Plantation Records, at the time. He worked with Riley in the recording of the Tom T. Hall demo song that Singleton saw potential in, "Harper Valley PTA." The record quickly became one of the best-known country music songs of all time. Riley was the first woman to hold the Number 1 spot on the Pop and Country charts at the same time.