George Best was refered to as the fifth Beatle for a time. Purely on the basis that he was a young, long haired british superstar at the same time as the fab four. All part of the swinging sixties, pop culture thing. Luckily, he was never tempted to try singing. George made a lot of poor decisions in his life but that was one wise one we can all be grateful for.
He did turn up in at least one film I can remember though. He had a walk on part in the film version of 'Til Us Do Part where he bumps into Warren Mitchell's Alf Garnett character in a pub toilet. Not exactly a career in the movies then, but it was at least a funny scene.