A Hard Day's Night (1964)
The Beatles--the world's most famous rock and roll band--travel from their home town of Liverpool to London to perform in a television broadcast. Along the way they must rescue Paul's unconventional grandfather from various misadventures and drummer Ringo goes missing just before the crucial concert. (IMDB Jim Beaver )
Currently rated a 7.7 on IMDB. I can't help but think that if it was The Critters rather than the Beatles in the movie that it would be a 3.5.