USA, 1984, 82 min. Rated R. Rob Reiner’s directorial debut has developed into a cult phenomenon. The film that invented the “rockumentary” has now outlasted most of the bands it mocked. Following the ill-fated American comeback tour of an aging heavy-metal group, this film has joined the ranks of the greatest comedies ever made. With Michael McKean, Harry Shearer, and Christopher Guest as David St. Hubbins, Derek Smalls, and Nigel Tufnel.