The Beach Boys and the Beatles are filling up the airwaves, but halfway between California and Liverpool, another band is putting together a sound that will change rock ''n'' roll forever. Andy Warhol discovers the Velvet Underground in a little tourist bar in New York, and he soon becomes the producer for this group whose songs aren''t so much about girls and hot rods but shooting up, alternative lifestyles, and the melancholy after the party. It''s the late sixties, but not quite everything is flower power. The radio wants nothing to do with the Velvets, but the cool kids know who they are, and the enormous influence of this short-lived band has yet to abate.