With no contract in view, Aimé Barelli, the leader of the band of the same name, decides to take a holiday. As this is the Holy Year, the young artist accepts to follow his mother on a pilgrimage to Rome. His band members - complete with their agent - decide to follow suit. Good idea because on the train to Rome, there is a whole class of charming schoolgirls, including charming Rosita and - surprise ! - Nicole, Aimé's pretty but elusive beloved. The trip is cheerful but eventful and life gets e...