I remember George and I going to see Blackboard Jungle. George was fifteen at the time and you had to be sixteen to go and see it. But I was sixteen, so I was all right. George’s mum was saying, ‘You’ll never get in, you’ll never get in,’ and we were saying, ‘Don’t worry, we’ll get him in.’ We went out in the back garden and got a bit of mud. George had the buddings of a little moustache so he rubbed mud on his moustache. We went along to the picture house and we got in. ‘Sure, he’s sixteen’… we spoke a bit deeper. The only reason we were going was because a Bill Haley song, ‘Rock Around the Clock,’ was in the film, that one song.
—  Paul McCartney in an interview with Paul Gambaccini, November/December 1973