Spending some time in jail for drunk and disorderly conduct turns out to be a life altering event for Larry Rhodes (Andy Griffith). While he’s in jail, Marcia Jeffries (Patricia Neal) stops by to broadcast her radio show and the sheriff makes a deal with Larry that he’ll be released early if he sings on the air. He agrees, and Marcia quickly realizes that his charisma and folksy charm would be a great hit on the radio. She nicknames him “Lonesome” and her uncle hires him to host the morning show at the radio station. Sure enough, Lonesome Rhodes is an instant sensation. Meanwhile, Marcia is becoming more and more smitten by Lonesome Rhodes and although he comes onto her, she turns him down. The only man in town competing with Lonesome for Marcia’s attention is Big Jeff, who is running for mayor. When Lonesome becomes jealous of him, he successfully convinces his audience to take Big Jeff down a peg and for the first time, Lonesome realizes just how much power he wields over his audience.
Lonesome quickly works his way up from small town radio personality to television personality in Memphis. While doing his show in Memphis, he ends up making fun of the sponsor and is yanked off the air. The crowd protests, the sponsor realizes their sales are actually up because of Lonesome Rhodes, and he is given his job back. Not only does he get his job back, but someone who works for the sponsor manages to get Lonesome his own show in New York. His New York show is sponsored by an energy pill, Vitajex, and sales soar when it’s being pitched by Lonesome Rhodes.
Lonesome becomes completely and totally drunk on power and fame. When he isn’t on camera, he makes fun of his audience, treats his staff badly, and even stabs Marcia in the back when he suddenly marries a young majorette (Lee Remick). When Lonesome is introduced to a senator in the midst of a failing presidential campaign, Lonesome becomes the senator’s media consultant and, once again, the Lonesome Rhodes touch proves to be golden. However, what goes up, must come down and Marcia takes it upon herself to destroy the monster she helped create. While the end credits of his show are rolling, Lonesome’s microphone would be cut off. But when Marcia was left alone in the control room, she turned his microphone back on and revealed Lonesome’s true thoughts about his audience to millions of viewers. Oblivious to what has just happened, Lonesome returns home expecting it to be filled with dignitaries, only to find an empty penthouse.