 good while chuck berry listens over the phone thereby inventing rock and roll in the original version the dancing by the students is so overzealous that an elderly teacher calls the cops to report a riot on his way out marty tells the band to never play that song again as he doesn't want to mess with history thinking rock and roll will happen on its own except it doesn't and when marty goes back to the future he learns that mambo is the most popular genre of music with rock and roll having never been invented not only that but the entire world is different thanks to professor