There’s a party at Delray’s, an underground African-American Rock and Roll bar in 1950’s Memphis. Huey Calhoun, a white man, arrives on the scene. The regulars begin to leave, but Huey convinces them to stay, claiming he is there for the music. Later, Huey is about to be fired from his job as a stock boy at a local department store, but he makes a deal with the owner – if he can sell 5 records by playing them over the speakers, he can have a sales job. Huey plays a Rock ‘n Roll hit and sells 29 records in a matter of minutes, but the store owner fires him anyway, incensed at the type of music being played.
Huey returns to Delray’s club, and begins flirting with Felicia, Delray’s talented sister, and promises to get her on the radio. Huey then proceeds to apply for DJ jobs at various local white radio stations. One of the owners, Mr. Simmons, invites him in, saying he’ll show him what a “real” DJ looks like. Huey hijacks the mic, and plays another African-American rock song. Mr. Simmons is about to have Huey thrown out, but then dozens of teenagers start calling in demanding more of Huey and his music. Mr. Simmons agrees to give him a two-week trial, and if he’s successful, he’ll get hired full time. After a few days, Huey is told to read an advertisement for beer, but he is illiterate. Huey asks Bobby, a friend of Delray’s with a janitor position, to tell him what it says. He forgets the exact words almost immediately and begins to improvise, ending with the phrase “Hockadoo!” Mr. Simmons again almost fires Huey, until the manager of the store advertised calls in saying that he wants Huey to do all of his advertisements, seeing as his stock sold out in minutes.
Huey’s station gains immediate popularity, as does his new catch phrase, even though no one understands what it means – including Huey. While on the radio, Huey encourages white people to go down to black churches, and they begin to do so. Meanwhile, Delray has saved enough money to put Felicia’s voice on the record, and she travels to Huey’s house to tell him this. He is overjoyed and promises to play it the next day. Huey’s prejudiced mother, however, breaks the record, which leaves Felicia heartbroken, but Huey tells her to come down to the radio station anyway. The next day, Huey brings in a band and back-up singers to play for Felicia live. Despite her reservations, Felicia sings and becomes an instant sensation. Felicia and Huey’s relationship begins to grow, and Delray is becoming more and more infuriated with Huey. He warns him of the danger of what he is doing, threatening to harm Huey if anything happens to Felicia.
Huey’s radio popularity grows more and more as white teens and black teens begin to accept each other. Huey and Felicia have been carrying on a secret relationship since the day she sang live on the radio. Two years later Huey proposes to Felicia on the way to a party at Delray’s. She says no because of laws and prejudice, but admits that without those obstacles she would accept. As the two share a kiss, a gang of white men pass by, spotting this. They hold Huey down as they beat Felicia with a bat. Huey manages to carry her into the club, crying out for help. Delray tries to go after Huey, for he promised to harm Huey should Felicia get hurt because of him, but Gator, a friend who has not spoken since he saw his father lynched as a child, calms him and sends out a prayer for change as Delray takes Felicia outside and gets her into the ambulance that was called.
Time has passed, and Huey is about to open his new TV show, a rock ‘n roll variety show featuring all African American dancers. Felicia is supposed to be his first guest, but she backs out at the last minute, fearing that people will think she and Huey are in a relationship. Huey informs Bobby that he will fill in, and after getting over some jitters, Bobby brings the house down. Felicia’s popularity is also beginning to grow around Memphis, as does her relationship with Huey. Felicia tells Huey that if they went to New York they wouldn’t have to sneak around all the time, but Huey insists that they are happy the way they are and don’t need to leave. She has been discovered by a talent agency in New York, as has Huey’s TV show. The agency wants them both to come up to New York, although Huey has to compete with a local Philadelphia DJ, Dick Clark, for the national show. They ponder the decision, and are even supported by Huey’s mother, who has changed her racist ways after seeing an African American church choir.
Huey is told he has won the TV position, if he agrees not to use African American dancers. Huey refuses, and proceeds to strip out of his suit on the air. Felicia tells Huey that she plans to go anyway, as it is her dream. In a desperate attempt to keep her, he kisses her on the air, and says he loves her. The feed is cut, and Huey is fired on the grounds that no one would watch his show if they knew about him and Felicia, and that he wasn’t the only white person to play black music anymore.
Felicia is taken away by Delray in an attempt to save her career. Now unemployed, Huey leaves the station and ponders his relationship with Memphis, realizing he couldn’t leave for any reason. Four years later, Huey is a DJ on an obviously low budget and low rated station (he jokes that they have “exactly one listener”). Felicia walks in, about to start a national tour. She tells Huey that she is engaged to a man named Bill, but that she wants him to join her on stage one last time. He refuses, afraid that no one will remember him. She begins her performance, and halfway through the song Huey walks on stage, and finishes the song with her to thunderous applause. He then proclaims “The name is Huey Calhoun. Goodnight and HOCKADOO!”