THE ROCKY HORROR PICTURE SHOW (1976). This horror-camp extravaganza still draws midnight crowds. Its story of two dorky, all-American kids (Barry Bostwick and Susan Sarandon) who find themselves indoctrinated into the pansexual ways of Dr. Frank-N-Furter is no more outrageous than La Cage aux Folles, but only a curmudgeon would deny the magnetism of Tim Curry, whose lip-smacking rendition of "Sweet Transvestite" remains one of the high points in all of cult movies. Jim Sharman directs. (100m) Saturday midnight at the Harvard Square.