According to Paul McCartney, he and John Lennon were underage when the film was released, and sneaked into the theater by wearing fake mustaches to make themselves look older. The movie is one of their earlier musical influences.
In this film, Eddie Cochran performs "Twenty Flight Rock". That song's influence was so great across the Atlantic in Liverpool, England, that Paul McCartney's ability to memorize the words and perform the song impressed John Lennon enough to ask him to join his group, then known as "The Quarrymen", which later became The Beatles.
On 9/18/68 The Beatles interrupted recording "Birthday" at Abbey Road Studios so they could go back to Paul McCartney 's house to watch the British TV premiere of the film.
Producers wanted Elvis Presley to perform in the movie, but Tom Parker demanded too much money for Elvis to sing one song.
The wedding dress that Jayne Mansfield wears was loaned to her to use for her real-life marriage to Mickey Hargitay in 1958.