Senza tregua il rock and roll

A frustrated big-band promoter runs in to rock-and-rollers Bill Haley and the Comets at a small-town dance. He quickly becomes their manager and, with the help of Alan Freed, hopes to bring the new sound to the entire country. But will a conniving booking agent, with a personal ax to grind with the manager, conspire to keep the band from making the big time?