The news that Conrad Birdie, a rock-n-roll idol, is to be drafted creates a national crisis among his teenaged worshipers and spells doom for Albert Peterson, an impoverished songwriter who wrote the title song for a film Conrad had planned to make.  Adding to Albert's woe are the attempts of his domineering mother to break up his romance with Rosie DeLeon, his long-suffering secretary.

In an effort to solve the dilemma, Rosie induces Albert to write a special farewell song that Conrad will sing to a fan on the Ed Sullivan show.  The lucky girl selected to receive a parting kiss from Conrad is 16-year-old Kim McAfee of Sweet Apple, Ohio.  But the singer's arrival there creates a near riot.  Kim's boyfriend Hugo Peabody, becomes jealous, her father refuses to let Conrad stay in his home and, even worse, Albert's mother arrives on the scene.

The final blow comes when word arrives that Albert's spot on the TV show will be limited to 30 seconds because the Russian ballet troupe scheduled to appear before Conrad needs an extra 4 minutes.  In desperation, Albert and Rosie slip some pills that speed up nerve reflexes into a glass of milk; the Russian conductor drinks it, and the ballet turns into a farce.  Conrad performs Albert's song, but as he sings to Kim, Hugo socks the singer on the jaw in full sight of all.  All ends happily, however, as Kim is reunited with Hugo, Albert finally decides to marry Rosie, and even Mama finds a Sweet Apple resident who wants to marry her.